Ordnance Instructions for the United States Navy. / 1866. Fourth edition.

by United States. Navy Department. Bureau of Ordnance

PART III.

CHAPTER I.

ORDNANCE AND ORDNANCE STORES.

1. All articles of Ordnance and Ordnance Stores, when duly delivered at any Navy Yard, are to be borne on the books of the Inspector of Ordnance, and duly accounted for, according to such regulations as may, from time to time, be established by proper authority.

2. He will make monthly estimates and requisitions for all materials and articles which may be required by the master workmen in the Ordnance Department, and which he may deem necessary; which requisitions are to be forwarded to the Chief of the Bureau for his approval.

No articles are to be purchased without previous requisitions, nor any to be used until duly inspected, approved, and receipted for.

Before reception, every article shall be carefully examined by the master workman in whose department it is required, and such other person as the Inspector shall appoint, and compared with samples, to see that it conforms to the standard, and is, in quantity and quality, as called for by the requisition or order of the Bureau for its delivery.

He will keep on hand standard Patterns and Drawings, approved by the Bureau of Ordnance, to which all articles of manufacture or issue shall strictly conform; notifying the Bureau of any discrepancies therefrom in articles received from other Yards, that unauthorized variations may be checked and the manufactures of each Yard be identical.

3. The Inspectors of Ordnance at all Navy Yards shall have the immediate custody of all articles appertaining to ordnance, and they shall be kept in suitable places, separate from the other articles in the Yard.

And they will promptly inform the Bureau of all orders received from Senior Officers, which may in the least affect the execution of the instructions given by the Bureau in relation to their duties.

4. Inspectors of Ordnance having charge of the articles above mentioned are, under the direction of the Commandant of the Yard, to be responsible for their being carefully attended to, and preserved from injury.

5. Whenever any of them shall require repairs, other than those which can be made in the ordnance workshops, the Inspector will apply to the Commandant of the Yard, or to the Bureau through him, for the necessary means to keep all articles in his charge in order and ready for service.

6. He shall require from master workmen employed on ordnance work reports in the required form (see blank forms) of the expenditure of materials and labor upon each and every object under their immediate superintendence, at which time they will make a return of all unexpended material on hand. They will also be responsible for all waste and improper use of material by those under their general superintendence.

7. The Inspector of Ordnance shall have authority over all master and other workmen employed on ordnance work, and direct all its details.

He will examine and certify to the correctness of all bills rendered for materials, supplies, or labor in the Ordnance Department, and examine and certify to the correctness of the pay-roll of all persons employed on ordnance work.

8. No Inspecting Officer or person employed by the Bureau is to show to, or leave in the way of persons not authorized by the Bureau, any drawing, descriptions, or dimensions of guns under contract, nor to permit the examination by such persons of the guns themselves.

9. The resident and other Inspectors are to inform the contractors of this strict requirement on the part of the Bureau, and to request them to cause it to be rigidly enforced by all persons under their control.

10. It is most positively forbidden to communicate any information whatever in relation to ordnance matters, or to show or describe ordnance work, of any description, to any person not in the employ of the government, unless by superior authority.

Inspectors are also directed not to hold correspondence in writing with manufacturers, contractors, or other parties in relation to ordnance supplies, unless specially directed by the Bureau.

Officers on Ordnance duty will give no official opinion, to Inventors or others, upon the merits of any invention appertaining to Ordnance, which may be submitted to them officially or unofficially for examination, unless by special direction of the Bureau of Ordnance.

All such opinions will be forwarded to the Bureau, to whom parties must be referred for information.

11. The Inspectors of Ordnance at the several Yards and stations are required to enjoin upon all their employés the strictest secrecy in relation to every thing connected with their duties. No information whatever is to be given to any one in relation to the prices of articles, the details of work, or the condition of ordnance or ordnance supplies.

Any breach of this order is to be followed by prompt dismissal from employment.

12. Whenever any ordnance stores shall be furnished to vessels, or for any other purpose, the Ordnance Officer shall take proper receipts for them from the officer to whom they are delivered. These receipts shall be signed at the Ordnance office, and the commander is required to ascertain before sailing if the proper officers have signed all receipts and vouchers.

13. The Ordnance Officer will deliver with them an Invoice of the number and cost of such stores, retaining a receipted duplicate, approved by the commander, to be forwarded to the Bureau of Ordnance.

One Ledger, one Invoice, and twenty blanks for Quarterly Returns to the Bureau of Ordnance, are to be furnished each vessel fitted for sea.

If any articles are purchased abroad, or obtained from other stations after the vessel is regularly fitted for sea, they should be duly entered in the Ledger, and a note made therein stating when, and from what source received; and, if practicable, their number and cost should be inserted in the Invoice of other articles supplied the vessel.

14. A separate list shall be furnished to all commanders of vessels of the ammunition furnished, which list is to be returned to the Ordnance Officer of the Yard to which the vessel shall return, with any additional supplies which she may receive during the cruise entered on it.

15. The allowances which are prescribed for the different classes of vessels in the Table of Allowances are not to be exceeded, except by the express sanction of the Chief of the Bureau of Ordnance.

16. It shall be the duty of any commander of a vessel, before making or approving requisitions, to examine the allowance table and expenditure books, to see that the amount required, together with that on hand, does not exceed the allowance, and that the articles required are allowed. If these articles are not allowed, or are in excess of the allowance, but are, in his opinion, necessary for the use of the ship under his command, he will state on the requisition, opposite the article, "in excess of allowance," or, "not allowed," and the reason why considered necessary, before sending it to the Commandant of the Yard or Squadron for his approval.

In case he shall neglect so to do, the Inspector of Ordnance will only furnish the allowance, and shall return the requisition for correction, calling the attention of the approving officer to this neglect.

17. All Ordnance Stores, except the ammunition, shall be delivered to the Gunner, or other officer appointed to receive them, at the ordnance store-houses, the Inspector of Ordnance furnishing him with the means of transportation, and men for stowing them in their appointed places on board, when the crew are not available for this purpose.

In order to guard against the loss or misdirection of Ordnance Stores, which has frequently been found to occur whilst they were being transferred from the Ordnance Store-houses to vessels going into commission, or in the case of vessels landing their stores on returning from a cruise:

The Bureau directs that whenever Ordnance Stores of any kind are to be received from or delivered on board of a vessel, a responsible officer be present, whose duty it shall be to take an exact account of them and see them safely delivered at their destination, indorsing the Receipts and Invoices with his name.

For any loss that may occur in the performance of this duty, that officer will be held pecuniarily responsible; and whenever any stores are found to be missing, the name of the officer who superintended their removal is immediately to be forwarded to the Bureau.

The Inspector of Ordnance will be vigilant in seeing this order strictly carried out.

18. All stores landed from ships will be received at the Ordnance Store-houses, when all responsibility on the part of the officer delivering them shall cease, and a survey be held, as soon thereafter as practicable, to determine the quantity of stores, and the condition in which they are delivered.—(See form of survey.)

When the vessel returns to a yard to be refitted or to be laid up at the end of the cruise, her Ledger and Invoice are to be handed to the Ordnance Officer of the yard for his examination, and for the use of the officers who may be ordered to hold a survey upon the Ordnance Equipments and Stores; and when the survey is completed, both Ledger and Invoice are to be forwarded to the Bureau of Ordnance with the report of survey.

19. It having been found that in the "Reports of Survey" made at the different Navy Yards on the Ordnance Stores of vessels returning from sea, many articles are put down as "deficient by Returns" without these deficiencies being in any way accounted for, the Bureau directs that the Surveying Officers shall require the Gunner (or other officer having charge of the Ordnance Stores, in case there be no Gunner on board) to show a just cause for said deficiencies; a statement of which, properly signed, is to be forwarded to the Bureau with the Report of Survey. In case of his failure to do so, he will be held responsible for the loss, and the value of the deficient articles checked against his pay.

Where arms or other articles are lost or destroyed in action, the fact must be properly authenticated by the signature of the Commanding or Executive Officer.

20. Ordnance Ledgers of all vessels coming from a cruise shall be signed by the Gunner or Executive Officer and the officer in command before leaving the Yard or station.

Invoices and Receipts must invariably be given and taken of all ordnance, ordnance stores, equipments, and small arms, when transferred from the keeping of one officer to another.

And whenever any article of ordnance is lost or mutilated, the fact shall be reported to the Bureau, with all the circumstances of the case, and the value of the same will be deducted from the pay of the person having it in his possession at the time, unless sufficient reason for a contrary course should appear.

21. It shall be the duty of the Inspector of Ordnance (or of the officers who inspect a ship on her return from a cruise) to report to the Bureau the condition in which the articles under the charge of the Gunner may be transferred, that his care and attention may be properly known and appreciated.

22. Officers upon Ordnance duty at Navy Yards may correspond with the Bureau on subjects connected with Ordnance duties, forwarding their communications open, to the Commandant of the Yard for transmission.

23. The dates of all circulars, orders, telegrams, or letters to which reference is made in corresponding with the Bureau, shall be distinctly quoted.

And the same rule is to be observed in forwarding triplicate Bills, Bills of Lading, and Invoices, the date of the order or orders being written across the face in red ink; and the receipt of all telegrams must be immediately acknowledged.

24. The Commandants will, in forwarding communications, accompany them with such remarks or recommendations as they may deem proper, and at any other time make such suggestions as they may consider will promote the public interest.

25. In shipping or forwarding stores each box or package shall be numbered, and have the nature of its contents stencilled or marked on the outside, and noted on the Invoice. The Invoice should in all cases of shipment accompany the articles.

All stores intended for shipment to squadrons, shall be legibly and conspicuously addressed to the Commander-in-Chief of the squadron, and marked for that squadron.

INSPECTION AND PROOF OF NAVAL GUNS

26. All cannon for the navy, cast at private foundries, will be fabricated in strict accordance with the terms of the contract made with the Bureau of Ordnance, and subject to the inspection of an officer detailed to supervise the operations. (See "Instructions for the Inspection and Proof of Cannon, 1864," for further details.)

27. New guns are to be closely examined and measured, inside and out, for defects of metal or manufacture, and the results recorded in the prescribed forms by the Inspector resident at the foundry, as soon after being finished as possible, if he has not already done so in the various stages of manufacture, which is preferable, as the detection of errors which pass the limits of toleration may save useless subsequent labor. Internal defects of metal will, for instance, generally be betrayed by a close examination of the core-pieces. As rust tends to conceal defects, this examination of the guns is to take place before exposure to the weather. And previously to the final examination and proof of guns, they are not to be covered with paint, lacquer, oil, or any material which may hide defects of metal.

If it is ascertained that any attempt has been made to conceal defects, the gun or guns so treated are to be rejected without further examination.

As the water-proof, which is of great importance in detecting defects of metal not otherwise developed, necessarily succeeds immediately the powder-proof, and can be effectively applied only in fine weather, and when the temperature is above the freezing-point, final inspections are to be made at such times only.

DESCRIPTIVE LIST OF INSTRUMENTS REQUIRED AND USED IN THE INSPECTION AND PROOF OF GUNS.

28. 1st. A mirror for reflecting the sun's rays into the bores. Two will be required if the sun be in the rear of the Inspector.

2d. A lamp attached to a staff for examining the bores when the sun is obscured, or the guns are under cover.

3d. A standard cylinder gauge. This is a hollow cylinder of iron, turned to the least allowed diameter of the bore, and one calibre in length. It has a cross-head at each end, one of which has a smooth hole through its axis to fit the staff, and the other is tapped to receive the screw in the end of it.

D. Van Nostrand Publisher. Julius Bien, pr.

4th. A measuring-staff of steel or iron, in joints of suitable length, connected together by screws. Each joint is provided with a light brass disk, the diameter of which is 0.05 inches less than that of the bore. Through the centre of the disk there is a hole which fits upon a shoulder at the joint; the whole is so arranged that when the joints are screwed together the disks between them are held firmly in place, while the length of the staff is not affected by them. A steel point is screwed on to the end. When pushed to the bottom of the bore, the staff coincides very nearly with its axis. The outer joint is graduated to inches and tenths. A slide is made to play upon it with a vernier scale, graduated to hundredths of an inch. On the inner end of the slide a branch projects at a right angle, sufficiently long to reach across the muzzle face, and, when in contact with it, to indicate the precise length obtained from that point to the end of the measuring-point on the other end of the staff. A half disk of wood, made to fit the bore, with a groove for the staff to rest in, placed just inside of the muzzle, is useful in preventing any springing of the staff.

The point being taken off, the staff can be used with the cylinder gauge, to measure the distance to which the latter descends. But as the graduation is intended for the points, care must be taken in this case to allow for the difference.

5th. A chamber-gauge for verifying the shape and size of conical chambers.

The head should be made of close-grained, well-seasoned wood, and of the exact dimensions of the chamber. Two planes, crossing each other at a right angle, coinciding with the vertical and horizontal central sections, have been found better than a solid block. The edges should be bevelled. A metal socket in its centre connects it with the measuring-staff. Being pushed to the bottom of the bore, if the length coincides with that obtained by the point, it is obvious that the chamber is large enough, provided the cylindrical part has not been bored too deep, in which case a shoulder would be found at the junction. The edges of the gauge should be chalked before it is inserted. When withdrawn, if the chalk-marks are visible all around the chamber, it is evident the chamber is not too large. With slight modifications, this arrangement may be applied to the slope of cylindrical chambers, and to the curve at the bottom of the bore of any guns. Should the inspection of guns with conical chambers or slopes take place at the foundry, an examination of the chamber reamer will be very satisfactory. If found correct in size and shape, the impossibility of making the chamber too large will be apparent.

6th. A star-gauge, for measuring the diameters of the bores and of cylindrical chambers. This instrument is composed of the staff, the handle, and a set of points for each calibre.

The staff is a brass tube, made in three pieces, for convenience of stowage, and connected together, when required, by screws. Its inner end expands into a head, in which are placed four steel sockets, at equal distances from each other, which receive the points. Two of the sockets opposite to each other are secured permanently. The two others are movable. A tapering plate or wedge, the sides of which are cylindrical, runs through a slit in the head; an aperture in the inner ends of the movable socket embraces the cylinder, so that when the plate is moved forward or backward, the sockets are projected or withdrawn. The tapering of the plate has a certain known proportion to its length, so that if it is moved in either direction a given distance, a proportional movement is imparted to the sockets, and to the points which they contain. It is easy to see how, in this manner, a movement of .10 in. may increase or diminish the distance between the points .01 in. Therefore there would be no difficulty in estimating, to a considerable degree of accuracy, a difference of .001 in. between the points. In general, however, the distance on the plate required to move the points .01 in. is about .06 in. only.

A square sliding rod is connected with the tapering plate, and runs through the whole length of the tube, projecting some inches beyond the outer end. This rod has as many parts as there are joints in the staff, and, like them, connects by screws. Each section of the rod works in its proper joint, through a square socket at each end, and is prevented from falling out by pins. When screwing the joints together, if the ends of the rod are pressed up to each other they become connected by the same motion.

The staff is graduated to inches and quarters, so that the distance of the points from the muzzle of the gun may always be known. A centre line, starting from the centre of the upper socket, is marked upon the staff throughout its length.

The handle in use at present is of brass, made to fit over the outer end of the staff, and to connect with the sliding rod by a screw, having a large milled head at the outer extremity of the handle. It may be used on either joint, as required. A slit through the handle permits a part of the staff near the end to be seen beneath. A scale on one side of the slit is graduated with the distance that the rod moves, to throw the points .01 in. apart.

That part of the handle containing the slit and scale is separated from the other part; it is made to fit closely over it. On each side there is a small tube; a thread is cut in one, through which a fine screw, held by a stud on the permanent part of the handle, works and gives it motion; a guide runs through the other. Seen through the slit is a small plate of silver inserted in the staff, and a fine mark upon it to show the place of zero, when the points are adjusted. The zero-mark on the scale is made to correspond with it by means of the screw just mentioned.

The points are of steel, with a strong shoulder at one end, below which the screw is cut that fits into the socket in the head. A wrench is made to fit the other end, so as to turn the point firmly into its place. They are made of such a length that they will just pass into the adjusting-ring when they are all in place. To this instrument belong the adjusting-rings and the muzzle-rest in the form of T; of the rings there is one for each calibre, reamed out to the exact minimum diameter of the bore. The latter can be used for any class of guns. Its office is to keep the staff of the star-gauge in the axis of the bore. For this purpose it contains a groove, above the perpendicular branch, to receive the lower half of the staff. There is a movable slide on each branch, which can be adjusted to marks for each calibre, so that points projecting from their rear will enter the muzzle and hold the rest in place. In this position the upper edge of the transverse branch coincides with the diameter of the bore.

A hook is pivoted on the inner side of the transverse branch, on one side of the groove, and so fitted that when the star-gauge is in the gun, it embraces one-half of that portion of the staff which is above the groove. Therefore, if the transverse branch be placed so as to coincide with the axis of the trunnions, the hook thrown over the staff, and the latter turned so that the centre line just meets the end of the hook, the perpendicular points will be perpendicular to the axis of the trunnions. If the staff is then drawn out carefully, the measurements will all be taken in the same plane. A notch in the end of the hook, made to coincide with the plane of the muzzle, may be used for marking the distances on the staff.

The upright branch is movable, and is made to fit into the end of the transverse branch, for convenience and security in packing.

In examining the bores after proof, it has been found that the greatest indentation occurs in general near the seat of the projectiles. But, as it is not always found at precisely the same point of the circle of the bore, a convenient mode of searching for it is desirable. This is supplied by a disk for circular measurements, which may also be considered as belonging to the star-gauge. It is made of composition, and is divided into halves, with a hole through the centre to receive the staff of the star-gauge.

It is turned so as to fit into the muzzle of the gun closely, with a projecting lip two or three inches broad to hold it in place, and with cleats overlapping the edges, to keep it from going in too far. The face is a plane surface. The circumference is divided into as many equal parts as may be thought desirable, which are numbered in regular order. The centre hole is reinforced on the inside by a projection which is turned to receive a collar that fits closely around it, and holds the two halves together when they are placed on the staff.

When ready for use, the face is in the plane of the muzzle-face. Its zero-mark is made to coincide with a light punch-mark on the muzzle-face, directly below the line of sight.

On the staff of the star-gauge a brass slide is fitted, having a thumb-screw to hold it in any position; from the inner end a point extends at a right angle to its axis, of sufficient length to meet the points at the circumference of the disk; a centre line extends from the base to the apex. The slide being moved so as to make its inner end coincide with any mark upon the staff, at which a circular measurement is required, and the centre line of the point being made to coincide with that of the staff, it is secured by the thumb-screw. The point of the slide is then in the same plane with the perpendicular measuring-points, and its direction always indicates them; a series of measurements, made before proof, may thus be compared with another made at the same points after proof.

It is obvious that the determinations will not be absolutely accurate, for when the gun is worn, should the stationary points be perpendicular, the movable points, being then horizontal, would fall below the true horizontal diameter, and the measurements would be more in error than it would be with the points in any other direction. Still, if care is taken to preserve the points at the greatest length possible, a very tolerable degree of accuracy may be attained. In the inspection of guns arranged on skids, the gun itself should be turned, which will insure accurate measurements. Care must also be taken not to allow the joints of the staff to become so loose that the coincidence of the centre line is destroyed when they are screwed together. If this should occur, however, a few turns of thread, placed between them at the time of putting the instrument together, would remedy the difficulty.

7th. An instrument for verifying the interior position of vents.

When the vent is drilled in the vertical plane of the axis, as in the guns of old patterns, a simple head, shaped to fit the bottom of the bore, or the chamber, with a staff fitted to it, is sufficient. But for the Dahlgren guns, with two vents, some other plan is better. The following has been found satisfactory:

A head of well-seasoned wood, which is fitted to the chamber, is attached to a wooden disk of the diameter of the main bore. The surface of the head corresponds with a longitudinal central section of the chamber; at the point where the projection of the vent would meet it a piece of hard wood is inserted. A central line drawn through its length, crossed at a right angle by another line at any known point from the smaller end, will afford convenient points to measure from. A stout square wooden staff is attached to the axis of the head; at a distance equal to the length of the bore, the end is jogged into the centre of a half disk of wood, which is fitted to the bore. The whole is so constructed that the straight edge of the half disk (or the chord) is in the same plane as a horizontal section of the head. A few holes are bored through the disk attached to the half head, to allow the instrument to pass freely into the gun and out of it.

A wire of untempered steel, of the size of the vent, with a sharp, well-centred point, and a small spirit-level, are required to use with this instrument.

The gun being levelled, and the instrument being pushed to the bottom of the bore, the upper edge of the half disk near the outer end of the staff is then brought to a level. The surface of the half head then corresponds with the horizontal central section of the chamber. The point of the wire being pushed gently to meet it, will show very accurately the interior position of the vent.

8th. Profile-boards for distances in front and rear of the base line.

Their lower edges are adapted to the shape of the gun, and the upper ones are parallel to the axis of the bore.

The distances from the base-line of the several parts, and of the points at which diameters are to be measured, are laid off accurately on the upper edge, and then marked in lines perpendicular to it on the sides and lower edges of the profile. An iron strip is attached to the upper edge to prevent warping, and the whole is well coated with shellac varnish, to keep it from absorbing moisture.

The following instruments are used in connection with the profile-boards:

A rule for verifying the marks, of such a length that not more than one fleeting may be necessary, to be graduated decimally according to the standard.

A small square of steel, to be used in referring the marks on the board to those on the rule.

A steel straight-edge, long enough to extend across the muzzle-face, and several inches on the board, to ascertain the extreme length from base to muzzle. It is also used for the same purpose at the extreme end of the cascabel.

A steel scratcher, to mark the gun at points not otherwise indicated, where diameters are to be measured.

9th. A trunnion-square of steel or iron for ascertaining the position of the trunnions, with reference to the axis of the bore. This instrument is a square with two branches, one of which is fixed and the other movable. The foot of each branch is in the same plane, and is parallel to the upper edge of the main piece which connects them. The latter is graduated to inches and tenths. The movable branch slides on the main piece, and may be secured to it by two thumb-screws. It is provided with a vernier scale graduated to hundredths of an inch. Between the branches there is a slide, also provided with a vernier graduated as before, with a thumb-screw to secure it firmly; in its centre there is a sliding-point, moving vertically, with a thumb-screw to fasten it. Above the foot of each branch there is a slit to receive the shank of a plate, on the end of which a thread is cut; the lower edge of the plate forms a right angle with the branch, and the plate is fastened to the branch by a nut, at a point from the end equal to the semi-diameter of the trunnion, which is marked on each branch.

When the feet of the branches, or the lower edge of the plates, rest upon the trunnions, the upper edge of the main piece is parallel to their axis, if their alignment is correct. When in the latter position, the edges of the feet will lie close against the sides of the trunnions.

A graduated steel wedge is used to measure the deviation of the trunnions from the feet of the square.

10th. A trunnion-gauge, which is an iron ring of the proper diameter of the trunnions. Its outer edge coincides with the diameter of the rimbases.

11th. A trunnion-rule, to measure the distance of the trunnions from the base ring, or line. This is an iron rod with a head at one end, through which passes one branch of a small square. The centre of the rod is marked on the end, and the square is set so that the inner edge of the branch which is parallel to the rod is at a distance equal to the semi-diameter of the trunnion from the centre. It is secured in this position by screws and clamps.

The upper side of the rod is graduated to inches and tenths. A slide with a slot through it, to show the graduation beneath, traverses upon it, and is kept from turning by a guide on the lower side. There is a vernier upon the slide, graduated to hundredths of an inch; a thumb-screw serves to secure the slide at any point on the rod. That end of the slide from which the graduation of the rod commences has both of its sides drawn out, to form knife-edges; the knife-edges and the end of the slide are in the same plane. When the square at the end is placed on the trunnion, the end of the rod will touch its side at the point of its greatest diameter. The rod being held parallel to the axis of the bore, with the side of the head pressing the rimbase, the knife-edge will be in a proper position to fall into the base line when moved to find it.

12th. A beam-calliper for measuring diameters is a square of steel or iron, with two branches, one of which is fixed and the other sliding. The inner edges of the two branches, when pushed together, lie, of course, in contact with each other throughout their length. The beam is graduated to inches and tenths. A vernier is attached to the sliding branch, graduated to hundredths of an inch. The latter is provided with a thumb-screw, to fasten it at any point.

The length of the beam must be rather greater than the diameter; and that of the branches than the semi-diameter of the guns to be inspected, at their largest points.

13th. A cascabel-block is a wooden cylinder of the proper diameter of the breeching-hole, the size of which it is used to verify.

The opening between the jaws may be ascertained by measuring the iron block which is fitted to go between them, or by a template.

14th. A vent-guide, to be used with vents in guns of Dahlgren's pattern.

This instrument is made of bronze or composition. When placed upon the gun, one of its branches coincides with the curve of the cylinder, and the other, starting from its centre, lies along the cylinder in contact with it longitudinally. The lower edges of the branches are a right line and a curved line, making two right angles with each other. The length of that of the transverse branch is equal to the distance between the centre of the two vents. The rear surface of the transverse branch is curved and quadrilateral. Its sides are inclined, so that their rear edges show the exact direction of the vents. Every point in the upper edge lies in the same horizontal plane. The height is sufficient to permit the edges to give an accurate direction to the drill.

The upper edge of the other branch runs off in a sloping curve to its extremity.

A centre line is drawn through the lower edge of the longitudinal branch, and is continued upwards on the rear surface of the transverse branch to the top.

The guide being placed with its centre upon the centre mark of the gun, and the centre line of the longitudinal branch being made to coincide with the centre line scribed upon the cylinder, the rear lower edge of the transverse branch will then coincide with the base-line, its extremities will indicate the centres of the vents, and the rear edges of the sides will show their true direction.

15th. Vent-gauges of untempered steel wire, with shoulders to prevent them from slipping into the vent. One should be of the proper diameter of the vent, one of the greatest, and one of the least diameter allowed.

16th. A vent-searcher, a steel wire of the length of the vent, bent to a right angle at the lower end and pointed. It is used for detecting imperfections in the sides of the vents.

17th. A semicircular protractor of metal for measuring the inclination of vents, or for ascertaining their deviation from the guide.

18th. A set of templates for verifying the shape of lock-lugs, the angle of the rear sight mass, the curve between the base-line and the front of rear sight mass, that at the end of the cascabel, the bevel of the breeching-hole, the opening of the cascabel, and the shape of the muzzle swell.

If the inspection should take place at the foundry, the templates used in chipping might be verified and used for inspection.

For guns of Dahlgren's pattern, a bronze model, showing the shape of the lugs and rear sight mass, and the position of the vents, is furnished as a guide to the contractors.

19th. A standard foot-rule for verifying measures.

20th. A foot-rule of steel for measuring the masses, the length of the trunnions, and for other purposes. The graduation should be extended to each end.

21st. A set of ring-gauges, large, medium, and small, for inspecting the projectiles used in proof.

22d. A small beam-calliper, with outside edges, for examining the adjusting rings and the ring-gauges.

23d. A platform balance, for weighing the projectiles used in proof, and for bringing the shells up to the standard weight. For use with the above there should be provided a bag of dry sand, a funnel, some wooden plugs for the fuze-holes, and a hammer.

24th. A set of implements for loading and cleaning, viz.:

A rammer, faced with hard wood or metal, with a graduated scale on the staff, near the muzzle, to show the distance of the front of the projectiles from the muzzle.

A bristle sponge with a worm in its end, for ordinary use in firing.

A sheepskin sponge, for drying the bore after cleaning it.

A gun-scraper.

A ladle.

A boring-bit.

A priming-wire.

A lock and lanyard, should navy primers be used in firing; but if friction primers are used, then a lanyard with a hook in its end will be required, only.

A breeching and a couple of tackles, if the guns should be fired on skids.

Six handspikes.

Six buckets and a large tub, for washing out the guns.

If the firing is made into a butt, a couple of wheelbarrows, with two or three pickaxes and half a dozen shovels, will be necessary.

25th. A searcher, with six or more points, to detect injuries or cavities in the bore.

26th. A machine for taking the interior impression of vents.

This consists of a wooden head, one-half of which is cylindrical, and the other half is of the shape of the chamber, both being rather smaller than the parts of the bore that they are intended for. A staff, flat on its upper side, and rounded on its under side to fit the curve of the bore, is mortised into the circumference of the cylindrical part of the head. A mortise is cut through the chamber part of the head, extending several inches in rear and front of the position of the vent. Into this mortise a loose piece is fitted, capable of free motion upwards and downwards, the top of which is pierced with holes to secure the wax or composition which is spread over its surface. This movable piece rests on a wedge attached to a flat rod running through a slot in the head; there is a slot in this rod about four inches long, a pin passing through it into the staff. To use the instrument, withdraw the rod as far as the slot will permit, which will allow the movable piece on which the composition has been spread to drop below the surface of the head, and protect it. Push the head to the bottom of the chamber, and arrange the position of the staff so that the movable piece will cover the vent, then press the end of the rod home. This motion will throw out the composition, and a distinct impression of the vent and of fire-cracks (should there be any) will be left upon its surface; draw the rod back as far as the slot will allow, and withdraw the instrument: the impression, being protected thereby, will come out uninjured.

Impressions of injuries or cavities in the bore may easily be taken by a similar contrivance.

27th. Hydraulic pump and apparatus for the water-proof.

Any of the various patterns of this machine may be applied to the proof of guns. An iron cross-head is secured to a stout wooden block which fits into the muzzle, and which has a flange or shoulder to cover the muzzle-face; rings of caoutchouc or gutta-percha are placed between them; an iron rod with a ring in one end, to fit over the trunnion, and with a thread cut on the other end, is used on each side of the gun, to connect the trunnion with the cross-head. The whole is set up with nuts, and the pressure upon the rings makes a tight joint; a coupling upon the cross-head receives the hose, and the water is forced into the gun through a hole in the wooden block. Care should be taken that the valve is loaded with the proper weight for proof.

28th. Dies for marking guns.—A full set of figures, with such capital letters as may be required for the inspection-marks; these should be one inch in length. Also, small letters of suitable size to mark "lbs.," and a full set of half-inch figures.

USE OF THE INSPECTING INSTRUMENTS.

29. The guns having been freed from rust, and their foundry numbers noted, in the order of their relative positions, on the field-book, the inspecting officer will proceed to verify the instruments to be used in their measurement, if this has not been previously done in a manner entirely satisfactory to him.

He will then examine carefully the guns, inside and out, for defects of metal or of manufacture, and note the results.

The interior of the bore is to be examined by reflecting the rays of the sun into it from a mirror or mirrors; or, if the sun is obscured, and there can be no delay, by means of a spirit-lamp, or of a wax taper, on the end of a rod, taking care not to smoke the surface of the bore.

The cylinder-gauge is then to be introduced, which must pass freely to the bottom of the cylindrical part of the bore. If obstructed, the depth to which it reaches should be noted.

The star-gauge is used to ascertain the exact diameter of the bore, and of the cylindrical part of the chamber. The bore must be measured at intervals of 1/4 inch from the bottom of the cylindrical part to the seat of the shot; of 1 inch from that point to the trunnions; and of 5 inches from the trunnions to the muzzle. If any marks of the reamer or other defects are seen in the bore, they are to be searched for, and their depths and positions noted. These results are to be tabulated according to the blank forms furnished. The whole length of the bore is ascertained by means of the measuring-staff, with the point screwed on, supported in the axis of the bore by the disks and half-tompion.

In the absence of this instrument, a pine rod, having the proper length of the bore marked on it, and the end rounded to the curve of the bottom of the bore, will answer as well, using a thread or a straight-edge across the face of the muzzle.

The shape and dimensions of the chamber, and the position of the interior orifice of the vent, are verified by means of the chamber-gauge, the description of which will explain its use. An inspection of the chamber-reamer will be generally satisfactory in determining the size and shape of the chamber.

The vent is measured by the appropriate gauges, the smaller of which must enter freely, and the larger not at all. It is searched for roughness, or for cavities in the metal around it, by means of the searcher, the point of which should feel every part of it carefully.

Its inclination to the surface, and its position externally, are verified by means of the vent-guide furnished for the Dahlgren guns, and by the semicircular protractor and the vent-gauge.

In guns of the ordinary construction, the position of the vent is marked on the profile-board, and its inclination to the surface is determined by the protractor and vent-gauge.

The exterior lengths of the gun are measured by the profile-board, marked with the true dimensions, the differences being measured by the foot-rule, or, if minute, estimated by the eye.

The exterior diameters are measured with the calipers and square, or by the set-gauges used in turning, and a graduated wedge.

To verify the position and alignment of the trunnions of a gun, it is first necessary to ascertain, by means of the trunnion-gauge and of the calipers, their cylindrical form and their diameters, which should be the same, or allowance must be made for half the difference in measuring their axial distances from the base-line, by the trunnion-rule, which should next be done. These distances should be equal, or their axes do not coincide—an error not tolerated.

The trunnion-square is then placed upon the trunnions in the plane of their axis. The feet of its branches should coincide with the surfaces of both trunnions, throughout their length, above and in rear, and their inner edges with the faces of the rimbases. Then, with the beam-compass, scribe on the upper surface of the gun the distance of the axis of the trunnions from the base-line, and push the sliding-point of the square down, till, at that distance, it touches the surface of the gun, and screw it fast. Then turn the gun over, and again scribe on it the same distance from the base-line. The square, being again applied, will determine whether the trunnions are above or below the axis of the bore, which will coincide with that of the gun, if accurately bored, and turned on the same centres and bearings. If the branches rest upon the trunnions before the point of the slider touches the gun at the scribe, their axis is below; but if the point touch first, above the axis of the bore, by half the space between. The graduated wedge, being placed under the vertical sliding-point, will determine the amount. If both touch at once, both axes are in the same plane.

No gun can be received, the axis of the trunnions of which is above that of the bore.

The lengths of the trunnions are measured with the foot-rule, and the diameters of the rimbases by that of the exterior rim of the trunnion-gauge.

If the alignment of the trunnions be correct, it will serve as a means of determining the correctness of the line of sight, which, before the gun is removed from the lathe, should be distinctly traced on the sight-masses and the swell of the muzzle, and should be at right angles to the base-line, to the axes of the trunnions, and to the connecting piece of the trunnion-square, when its branches rest against their rear, with the plates across their upper surfaces.

The Inspector will further satisfy himself of the correct tracing of the line of sight on the gun, by examining the lathe and the manner of tracing it in the plane of the axis of the bore, at right angles to the axis of the trunnions, as by it are placed the sights and vent, and in their absence it serves as a line of metal sight.

The positions of the sight-masses are verified by the profile-board, and by reference to the line of sight, traced on them; their form and dimensions by the templates.

The positions of the lock-lugs and their forms are verified by means of the bronze pattern furnished to each foundry for each class of the Dahlgren guns, and their dimensions by the templates. For other guns the position of the lock-piece is marked on the profile-board, and their measures taken as above.

The opening of the cascabel and its curves, and those of the breech and the muzzle-swell, are verified by means of the "cylinder-block" and the templates.

30. The following variations from the proper dimensions may be tolerated by the Inspector, though every effort should be made to conform exactly to the drafts furnished by the Bureau of Ordnance.

In the diameter of the bore			{	more			0.03
				less			0.00
Exterior diameter			{ {	where turned	}	more	.05
				or planed		less	.05
				where not	}	more	.20
				turned or planed		less	.05
In the length	{ {	of the bore, more or less					.10
		from rear of base-ring or line to face of the muzzle, more or less					.25
		of the cascabel, from rear of base-ring to the end, more or less					.20
		of the reinforce, more or less					.10
From the axis of trunnions to base-line, more or less							.05
In the length of chamber, more or less							.10
In the position of the axis of the trunnions			{	above axis of the bore			.00
				below axis of the bore			.20
In the length of trunnions, more or less							.05
Diameter of trunnions, less							0.05
In the same gun, no variations to be tolerated in the position of the trunnions, or in their alignment.
In the vent	{	diameter more					0.025
		do. less					.000
In lock-piece any dimensions			{	more			.10
				less			.00
Variation of position of exterior orifice of vent							.05
Idem of interior orifice of vent							.20
In the length	{ {	in the bore or vent					.00
		on exterior surface of reinforces, where turned or planed					.10
		elsewhere, where turned or planed					.25
		on trunnions, within one inch of rimbases					.10
		on trunnions, elsewhere					.25
Enlargement or indentation of bore by proof, not to exceed							.02

The measures are to be taken by scales corresponding with the standard measures of the United States.

If two or more cavities should be near each other on the exterior, the gun may be rejected, though the cavities should be of less depth than tolerated in the table.

If the trunnions are placed within the limits of toleration, the preponderance must not vary more than 5 per cent., more or less, from that fixed in the contract.

POWDER-PROOF.

31. The proof-charges shall be as follows:

Calibre and Class of Gun.			Charge of Powder.	Projectile.	Wads.	No. of Fires.
Shell-guns.			Pounds.
	XV-inch	43,000 lbs.	35	Shell 330 lbs.		3
			45	Shell 330 lbs.		3
			55	Cored sh. 400 lbs.		3
	XI-inch	16,000 lbs.	25	Solid shot	Gromet	1
			15	Shell		10
	X-inch	12,500 lbs.	18	Solid shot	Gromet	1
			12	Shell		10
	IX-inch	9,000 lbs.	15	Solid shot	Gromet	1
			10	Shell		10
	8-inch of 63 cwt., or	7,000 lbs.	12	Shot	Gromet	1
			10	Shell		10
	8-inch of	6,500 lbs.	10	Shot	Gromet	10
	8-inch of 55 cwt., or	6,000 lbs.	10	Shot		1
			10	Shell		10
	32-pdr. of	4,500 lbs.	8	Shot		10
Shot-guns.	130-pdr. of — cwt., or	16,000 lbs.	30	1 Shot	Gromet	10
	64-pdr. of 106 cwt., or	12,000 lbs.	20	do.	do.	10
	32-pdr. of 57 cwt., or	6,400 lbs.	15	do.	do.	10
	32-pdr. of 51 cwt., or	5,700 lbs.	13	do.	do.	10
	32-pdr. of 42 cwt., or	4,700 lbs.	10	do.	do.	10
	32-pdr. of 33 cwt., or	3,600 lbs.	10	do.	do.	10
	32-pdr. of 27 cwt., or	3,000 lbs.	9	do.	do.	10

The cannon-powder for proof shall be of not less than 1,500 feet initial velocity, as determined by the gun-pendulum at the Ordnance Yard, Washington.

It shall be filled in service cylinders, and well settled.

For chambered pieces the increased charges should fill the chamber and necessary portion of the bore.

The projectiles shall be of full weight, and not below the mean gauge; the shells shall be filled with a mixture of sand and ashes, to bring them up to the proper weight of the filled shell.

Sabots for the shell and a gromet wad over the shot.

The gun should be fired on skids or a proving-carriage, to test the trunnions.

If five per cent. out of any lot offered for ordinary proof under a contract shall fail to sustain it, the whole may be rejected, as may be stipulated in the contract.

WATER-PROOF.

32. The pressure to be applied in the water-proof will be two atmospheres, or thirty pounds to the square inch.

The penetration of water in this proof through the metal of the piece, in any place, will cause the rejection of the gun; and if, on examination after the water-proof, there shall be any defects indicated by weeping or dampness in the bore, the gun shall be rejected.

The water-proof is alone to be depended on to detect minute clusters of cavities in the bore, which for this purpose should be perfectly dry, and examined by sunlight. All inspections, consequently, should take place in fair weather, and when the temperature is above the freezing-point.

MARKING GUNS.

33. Guns for the naval service, received by authority of the Bureau of Ordnance, are to be marked in the following manner, viz.:

On the cylinder, in the line of sight near the sight-mass, all accepted guns are to have stamped an anchor two inches long.

Drawings of these stamps will be furnished by the Bureau of Ordnance.

On the base ring or line, the initials of the foundry, the register number, and the weight of gun in pounds.

On the right trunnion, the calibre and year of fabrication.

On the left trunnion, the letter P. and the initials of the inspecting officer; all the above in one-inch letters.

On the upper jaw of the cascabel, the preponderance in pounds to be stamped lightly with half-inch figures.

On the end of the upper jaw, the cascabel block and head of the pin, the foundry number in quarter-inch figures.

The foundry number is also to be marked on the right rimbase.

Guns rejected for imperfections of any kind will have the letter C. stamped on the anchor, so as to partially obliterate it.

The founders are to be dissuaded from selling such guns to other parties, and required to break them up.

Guns rejected for such defects as render them dangerous to those who fire them, should be irreparably mutilated, with the consent of the founder.

EXTREME PROOF OF TRIAL-GUNS.

34. The extreme proof of guns intended for trial of metal, subject to such modifications by the Bureau as future experience may dictate, will be conducted as follows:

A suitable 'butt' shall be erected to arrest the flight of the projectiles used in proof, and to admit of their easy recovery, and a bomb-proof, readily accessible, for the protection of the firing party.

When practicable, the 'butt' should be made thick enough to allow the shot to just pass through, and be stopped by another beyond it, without penetrating the latter; this is, for XI-inch, about 12 feet.

With care, it is estimated that 130 shells may be fired 1,000 times, at the rate of one hundred rounds, per day.

After undergoing the ordinary proof established for its calibre and class, the gun selected for extreme proof shall be subjected to at least 1,000 rounds with service charges.

It may be fired from the skids, or suspended, as the Bureau may direct.

During the trial the gun shall be frequently and critically examined, inside and out, for cracks or defects, especially about the interior orifice of the vent, of which impressions are to be taken in wax at regular intervals, in the manner prescribed on page 16, or in such other manner as the Bureau may direct. If they show that the vent is corroded in furrows, and enlarged considerably in diameter at its junction with the bore, a permanent impression is to be taken in lead, to show the conical enlargement. The following manner, practised at the Experimental Battery at Washington, is recommended:

IMPLEMENTS REQUIRED.

35. 1. A soft wire about 0.07 in. in diameter, and 3 or 4 fathoms long.

2. A lever about twice the length of the bore, and about 3 inches in diameter, and shod to suit the curve of the bore nearly.

3. A small button of soft lead, judged to be of sufficient size to fill the vent at least one inch from the bore. This is to be pierced lengthwise to receive the wire.

TO TAKE THE IMPRESSION.

36. Shove the wire through the vent; let it pass along the bore and out at the muzzle; put it through the leaden button and tie a knot at the end. Draw the wire back through the vent until the leaden button is introduced firmly into the inner orifice.

Lith. by J.F. Gedney, Washn.

TYPES OF VENTS.

Apply the lever, making its shoe bear on the button, and force it well in by repeated blows, the muzzle being the fulcrum. This done, disengage the button by pushing in the priming-wire.

In taking impressions of the vent and cracks, each button in turn is used as a pattern for moulding its successor, allowing for the progressive enlargement of the vent, or the cracks emanating from it. When the crack shows itself, the head of the button should be so enlarged as to include it.

These examinations should take place after every twenty fires, at least, and more frequently when any unusual enlargement of the vent or extension of cracks shall be developed, and indicate its speedy destruction.

Before each examination the bore of the gun is to be carefully washed and dried.

In recording the measurements of the bore in extreme proof and after service, distinguish between "indentation," which is the depression at the "seat of the shot," which is always below, and the "wear of the bore," which is generally above, and increase of bore, or "enlargement" from any other cause.

When from the appearance of the bore at the interior orifice of the vent, and especially when a crack or cracks appear to be extending rapidly, the vent so enlarged may be filled with melted tin, zinc, or Babbitt metal,—a tight-fitting sponge-head being pushed to the bottom of the chamber to close the interior orifice,—and the other vent be drilled through for the purpose of continuing the firing.

The precise time at which this is to be done will vary, according to circumstances; such as quality of metal, charge, and elevation.

The endurance of a smooth-bored gun with service charges may be surely predicted by observation of the progressive wear of the interior orifice of the vent.

There are certain general forms in which this enlargement takes place. They may be classed as triangular, lozenge, quadrilateral, star, circular, and elliptic. (See Plate.)

With the ordinary central vent, when subjected to a rapid, continuous fire, the enlargement usually takes the form of an isosceles triangle, the apex of one of the angles towards the muzzle, and the other two perpendicular to it.

With the lateral vent of the Dahlgren system it usually takes the lozenge form, the cracks extending from the opposite angles lengthwise of the bore.

With those rifled cannon in which the vent is bouched, the cracks appear around the bouching; and although the bouching preserves the vent, yet the formation of fissures around the enlarged orifice, when once commenced, causes a greater tendency to rupture. With the vent not bouched, the wear in rifled cannon is about double that of the smooth-bore.

So long as the wear of the vent is regular and without cracks, a mere enlargement is not indicative of danger; but when it reaches a diameter of four-tenths (.4) of an inch the vent should be closed and a new one opened.

A gun of large calibre should not in service be expected to endure more than 400 or 500 rounds before it will be necessary to open the new vent, which, however, will be of no advantage, unless the old one be closed at its interior orifice, on which the gases would otherwise continue to act as a wedge.

The first distinct appearance of the cracks, as shown by the button, is the proper limit.

After the gun bursts, make a sketch or draft showing lines of fracture, and reserve specimens to be sent to the Ordnance Yard at Washington for trial of density and tensile strength; and, if practicable, a photograph should be taken.

Lith. by J.F. Gedney, Washn.

PREPARATION OF GUNS FOR SERVICE.

37. After the guns have been received at the Navy Yards it is necessary to adjust the sights, and, in the guns of the Dahlgren pattern, cut the screw hole in the cascabel.

CUTTING THE SCREW-HOLE.

38. The boring and screw-cutting machine is a convenient portable hand drill-press, the use of which is readily understood by any machinist.

The gun being carefully levelled, and the trunnions placed horizontal, the position of the centre of the screw-hole, which in the guns of the Dahlgren pattern is tangent to the radius of the breech, is marked on the neck of the cascabel with a centre punch.

The machine is placed on the cascabel, the boring shaft inserted in the hollow leading bar, and its movable centre placed on the mark. The instrument is then set vertical, by a spirit-level on the cogged driving-wheel, and the four pairs of set screws on the clamp-head embracing the cascabel.

The centre is then removed, and a drill inserted in the lower extremity of the boring-shaft, which, being held firmly by a shoulder and turned by a four-armed wrench, while pressed up to the metal by slowly turning the cogged driving-wheel, cuts the hole. This is successively enlarged, by two or more counterbits, to the size of the body of the screw.

The cutter is then inserted in the leading bar, and the thread cut.

ADJUSTMENT OF THE SIGHTS.

39. The bore having been thoroughly cleaned, the axis is levelled by a spirit-level; this may be very conveniently done by the aid of the levelling-bar. The axis of the trunnions is to be laid horizontal, either by placing a small level on the trunnions, or, as more exact, by using the trunnion-square. If the trunnion-square is used it will be proper to verify the position of the line of sight, which is frequently incorrectly placed at the foundries.

The breech-sight is then to be adjusted.

A brass head or tompion, fitted with a vertical arm, on which there is a ledge for a spirit-level, is then introduced into the bore, and the arm placed vertical by the spirit-level and a tangent screw.

The arm is pierced on its centre line with two holes—one at the height of the prescribed diameter of the muzzle, the other at a height equal to the proper distance of the bottom of the sight-notch from the axis of the bore. A waxed thread or fine wire, being stretched from the upper hole to the centre of the sight-notch, will coincide with the line of sight traced on the swell of the muzzle, the top of the reinforce sight-mass, and the base-line, if they are correctly placed. It will also be parallel to the axis of the bore if the adjustment of the breech-sight is exact, and the top of the reinforce-sight is made to coincide with it.

This is, however, seldom the case, and after the adjustment of the reinforce-sight it is necessary to verify it.

This is done by the levelling-bar—a square steel bar with parallel faces, somewhat longer than the distance between the sights, the rear end of which is bevelled at 60° (the angle at which the sight is placed).

The outer end of this bar is placed on the reinforce-sight, which has been previously adjusted to the proper height, and the bevelled end in contact with the outer face of the sight-bar. The bar is then levelled by two screws placed near the inner end, and a spirit-level on its upper surface.

If then the bottom of the sight-notch coincides with the bottom of the bar, the line of sight is parallel to the axis; otherwise, the reinforce-sight or the sight-bar must be lowered until coincidence is obtained.

A centre line on the bar verifies the coincidence of the line of sight, and also the motion of the sight-bar in the vertical plane. The bevel verifies the angle of the bar; and the distance between the outer faces of the sight-notch and of the reinforce-sight, being also marked on the levelling-bar, verifies this adjustment.

Another method is sometimes and more advantageously used in adjusting the sights of guns which have not been turned.

Two iron or wooden disks are turned to the exact diameter of the bore, and placed on a rod two or three feet longer than the bore. One of the disks is placed near the bottom of the bore, the other just within the muzzle. On the part projecting beyond the muzzle there is a double square, each arm of which is divided into equal parts and traversed by a fine slit.

The square being set vertical by a spirit-level or plumb-line, and a waxed thread or wire stretched taut from the outer arm through the slit, cutting equal divisions on each, and passing through the centre of the slit, it is evident that a line of sight is obtained through the centre of metal and parallel to the axis of the bore.

This method has the advantage of adjusting the sights in any plane parallel to the axis, as in the case of the side-sights of rifled and other cannon.

ADJUSTMENT OF THE SIDE-SIGHTS.

40. The gun having been levelled, and the trunnions placed horizontal, a centre line is to be drawn on the top of the left (or right) rimbase.

The support for the sight is then to be fitted to the breech, at the distance from this line marked on the pattern-sight for its calibre, with the bottom of the sight-notch in the bar, exactly the height of the front sight (one inch) above the upper surface of the rimbase; the sight-bar perpendicular.

It is advisable to place a very thin sheet of rubber under the support, to prevent the heads of the screws from being jumped off by the vibration. The screws have the same thread as those for the present reinforce-sight.

After the breech-sight is adjusted, a parallel to the axis of the bore is to be drawn in the usual manner, and the front sight screwed in on the rimbase.

Some trifling adjustment may then be required, to bring the height of the top of the front sight and the bottom of the sight-notch parallel to the axis of the bore in both the horizontal and vertical planes.

PRESERVATION OF GUNS.

41. Guns received at Navy Yards are to be carefully placed on the ranges of masonry, capped with iron skids or bars. It is intended that these shall be so high that the guns may be rolled upon them without their trunnions touching the ground, and that the earth will not be beaten up against their muzzles by heavy rains.

42. The surface over which guns are to be stowed should be kept firm and clear of all vegetation, and for this purpose should be covered with cinders from the smiths' forges, or other substance unfavorable to or destructive of the growth of plants and grasses.

43. In stowing the guns they should be made to rest on one of the skids or bars, a little forward of the base-ring, the muzzle depressed, but not so much as to prevent the use of the sponge to clean out the gun; the axis of the trunnion of each to be inclined the same way, and just enough not to touch the adjoining gun; the vents to be upwards.

44. Before the stowage is finally made they should be carefully and thoroughly cleaned from rust and all improper coatings, and be lacquered internally and externally with such composition as may be directed by the Bureau. This should be applied, when practicable, when the guns are well warmed by the rays of the sun. The vents and all screw-holes are to be stopped with plugs made of soft wood or oakum dipped in tallow, after they have been protected by an application of beeswax dissolved in spirits of turpentine, or other composition that may be directed by the Bureau.

45. No tompions are to be put into the guns when they are stowed unless expressly directed by the Bureau; if so ordered, a score must be cut out from them on the lower side, half an inch wide and equally deep.

46. In lacquering guns care is to be taken to leave the distinguishing marks and numbers distinctly visible.

47. Shell-guns are always to be denominated by the diameter of the bore; shot-guns by the weight of their shot.

48. Guns of the same calibre and class, when it can be conveniently done, are to be stowed in the same tier or range, and those of each class belonging to or selected for any particular vessel kept together. Each tier or range of guns of a particular calibre or class is to be marked accordingly with paint on a sign-board, and the first gun of each class belonging to a vessel is to be marked with the name of the vessel.

49. The Officer on Ordnance duty will examine all the guns in the yard and on board vessels in ordinary, at least once in every two weeks, and take care that they are kept protected from rust or any other injury, and will report to the Bureau whenever any additional precautions or arrangements are required for their proper preservation, and which may not be furnished by the order of the Commandant of the Yard.

50. No cutting, boring, or chiselling of guns is to be done at any time without express authority from the Bureau.

51. No condemnation of guns or small arms belonging to the Navy is to be made, except upon surveys specially ordered, and confirmed by the Chief of the Bureau; nor of other articles which have been furnished under his authority, or by his direction, unless by surveys ordered or sanctioned by him.

52. When guns and their equipments are to be put on board vessels for their armament, the guns are to be carefully and thoroughly cleaned and examined, to see that they are in all respects in proper serviceable condition.

The vents should be examined with the vent-gauges and searchers, to see that they are clear from any substance which may obstruct the use of priming-wires and primers.

53. The carriages are also to be carefully examined, the trunnion-holes and arms of the axletrees cleaned, and saturated with boiled linseed oil, the cracks filled with putty, and rubbed smooth, and the trunnion-holes black-leaded. The iron work should be freed from rust, all screws be made to work easily, and be well cleaned and coated with proper composition.

54. The Ordnance Officers will see that the sights are properly fitted and marked for their proper guns. The greatest care should be taken that they are properly adjusted, as the efficiency of the ship depends on it, and it is difficult to detect or remedy any error after they are placed on board; that the beds and quoins are fitted and adjusted, and the quoins graduated to degrees or distances to correspond with those marked on the sight-bars. Porter's quoin is adopted for all carriages requiring quoins.

55. New guns are to have locks fitted to them before being put on board ship. Those having two lugs will have the one on the right fitted; the other is to be left solid.

56. When the guns are to be shipped for transportation merely, the same precautions are to be taken to guard them from injury as on shore, with the addition of a wad dipped into the composition which covers the bore, thrust into the muzzle, and connected with the tompion by a lanyard.

In the transportation of guns by rail—unboxed—the vents are to be plugged with soft wood, puttied over, and turned vent downwards on the trucks. All bronze howitzers transported by rail shall be boxed.

57. At the termination of a cruise the guns composing the battery of every vessel-of-war of the United States, shall be carefully examined by the Ordnance Officer of the Yard, and such others as may be directed, with the view to discover and report any injuries which they may have sustained in service, or any defects which may not have been developed in the original proof. In this examination the attention of the Inspecting Officers is to be directed to the following points, viz.:

Enlargement of the interior or exterior orifice of the vent.

Indentations or hollows produced by the shot balloting against the surface of the bore, or by the action of the gases.

Cuts or scratches in the bore, produced by fragments of broken or the roughness of imperfect shot.

Roughness or corrosion of the metal on the exterior, produced by neglect or exposure.

Similar injuries in the bore, or any enlargement of the bore, which is to be ascertained by measuring with the star-gauge, at every one-fourth (1/4) of an inch from the bottom of the cylindrical part to the seat of the shot, every inch from that point to the trunnion, thence every 5 inches to the muzzle, and the results recorded in the usual form, and reported to the Bureau, that they may be compared with those noted at the original inspection.

In rifled cannon, cracks or injuries produced by firing, or the rupture of shells, are to be sought for:—

Around and in rear of the vent bouching;

On the top of the bore, between the trunnions and reinforce band.

On the lower side of the bore, near the seat of the shot, at the junction of the lands and grooves.

Near the inside of the muzzle, caused by explosion of shells.

Care is to be taken that the distinguishing marks and numbers are always accurately noted, that the correct history of each gun may be preserved.

58. Before sailing, the Inspector of Ordnance will furnish the commander with a descriptive list of his battery, together with a statement of the number of times each gun on board has been fired, in the following form; a copy of which the commander shall transmit to the Bureau before sailing: this list shall be returned to the Inspector of the Yard to which she may return, with all additional firing noted opposite the number of each gun, certified "correct" by the commander.

In the list furnished by the Inspector, if the "number of fires" is estimated, it is to be entered in red ink (See Arts. 62-64), and so carried forward in the subsequent returns.

NAME OF VESSEL.						STATION.
( )						( )
Class of Gun.	Marks on Base-Ring.			Trunnions.		Pivot, or Broadside.	Where Received.	Number of Fires to Date.
	Reg. No.	Weight.	Foundry.	Right.	Left.
Forwarded by						Commanding.

59. The Bureau directs that, whenever a gun is taken on board a vessel, the number of rounds which have been fired from it be ascertained by the Commander, a record made thereof, and forwarded with the descriptive list, in the above form, to the Bureau; and whenever a gun is landed or transferred to another vessel, a similar record is to be furnished the officer receiving it, which must be stated in the receipt for the gun, and a copy forwarded to the Bureau of Ordnance by the officer delivering the gun.

The Commander shall also transmit to the Bureau a quarterly return, according to the prescribed form (See [Appendix B, No. X.]) of all firing whether with or without projectiles, in action or otherwise; noting particularly the kind of shell, species of fuze, kind, charge, and name of maker of the powder used in the gun and shell. He shall take care to note also the number of premature explosions of shells, and the point at which they take place, with the supposed causes thereof.

60. The Inspector will also furnish the commander with a set of leaden impressions of the interior orifice of the vents of the guns, secured in a suitable box, that he may be able to compare the wear and gradual enlargement. These will be transferred with the guns to other ships or when landed.

61. The protracted firing to which the Navy cannon have been subjected, and to which they will continue to be liable, renders it necessary not to exceed the number of fires designated for each vent.

These must never exceed five hundred (500) fires for each vent.

In the IX-in., XI-in., and guns of similar form, the right vent is always bored through, and the left initiated sufficiently to give it direction.

When five hundred (500) rounds have been fired from the right vent, it is to be closed by filling it with molten zinc or lead, and the left vent is to be bored, which will require a skilful mechanic.

When the left vent has been fired five hundred (500) rounds, the gun is to be disused, as it will then have been fired one thousand (1,000) times.

It may happen, from some peculiarity in the nature of the iron, that the vent may be worn to its full extent before five hundred (500) rounds have been fired, in which case the vent is then to be closed, and the other vent opened.

The gun should be frequently and critically examined inside and out for cracks or defects, especially about the interior orifice of the vent, of which impressions should be taken after every ten shotted rounds in practice, and at the close of an action.

The instrument described on p. 16 is convenient, but by no means indispensable—any small spar, such as a boat's mast, or even the rammer handle with a curved piece of wood seized to the end, will, in expert hands, take an impression of the vent or crack equally well.

62. As the best indication of the amount of firing to which any smooth-bored gun has been exposed, when it is not otherwise known, is given by the enlargement of the vent, particular attention will be paid, in the reinspection of the guns, to this point. The standard gauge will be used to ascertain the general enlargement, and the searcher to detect defects which may have been developed in firing. Impressions are to be taken of the lower orifice of the vent with softened wax, and if they show that the vent is corroded in furrows and enlarged considerably in diameter at its junction with the bore, a permanent impression is to be taken in lead to show the conical enlargement. (See mode of taking impressions, [Arts. 35 and 36.])

63. When the number of rounds fired is not known, an estimate may be made from an examination of the vent by cylindrical gauges differing from each other by .01 of an inch passed through it. If the number is estimated, it is to be entered in red ink.

64. In all the guns of the Dahlgren pattern the vents are (.2) two-tenths of an inch in diameter. In all other guns .22 of an inch exterior, .2 of an inch on the interior.

Observation of the wear of the vent in proof firing of smooth-bored guns gives the following as the average diameter of the vent, after the undermentioned number of fires:

No. of rounds	100	200	300	400	500
No. of rounds	.24	.26	.30	.35	.40

These, combined with examination of the interior orifice, will enable a very correct judgment to be formed of the probable number of fires sustained and duration of the gun.

The larger the calibre and the heavier the charge the more promptly the wear is manifested on the interior and exterior.

This enlargement does not extend very far from the lower orifice until the enlargement on the exterior has reached a diameter of .3 of an inch.

65. So long as the wear is regular, and the cracks, although numerous, do not exceed .5 of an inch in length, the indications are good. If the cracks are but few or diminish in number, running into each other and extending rapidly, it is a very unfavorable sign. In the rifle cannon (Parrott's) cracks athwart the bore either running into the bouching or in the rear of it are very unfavorable to the gun's endurance.

66. Whenever any premature explosions of shells take place within the gun or near the muzzle, a careful examination of the gun shall be made; and all the circumstances of the case, together with the opinions of the commander and officers in immediate charge as to the cause thereof, reported to the Bureau; taking care to state the kind of shell and species of fuze used; the mode of loading; whether the shell was lined or coated on the interior; kind, charge, and name of maker of the powder which was used in the gun and shell.

There is reason to believe that few failures of the Parrott rifles have occurred where the guns have not been previously, or at the time, injuriously strained by the explosion of shells within the bore.

67. Whenever a gun shall give away under fire, or an accident of any kind happen to one, the Bureau desires to be immediately informed of all the facts in relation thereto.

Particular attention should be paid to the following points:

1. The manner in which the gun was loaded, stating the charge and kind of powder used, and character and weight of projectiles.

2. The condition and appearance of the gun after it gave way, and what effect was produced on the carriage by the explosion.

3. What injuries, if any, occurred to the crew of the gun or vessel.

Sketches of the gun and fragments which remain should also be sent to the Ordnance Yard at Washington for trial of density and tensile strength, accompanied by the written statement in detail of the officers in immediate charge of the gun, and if practicable a photograph should be taken.

INSPECTION OF SHOT AND SHELLS.

RULES AND MEMORANDA FOR THE GOVERNMENT OF INSPECTORS.

68. All shot and shells for the naval service must be—

1st. Made from gray or mottled charcoal pig-iron.
2d. This iron most not be blasted with anthracite coal.
3d. It must be poured into sand moulds.

69. After being cast in this manner, the shot and shells must be—

1st. Spherical.
2d. Smooth on the surface.
3d. Free from the defects named in the following rules for the use of the inspecting instruments:

FOR SHOT.

70. Inspecting Instruments.—One large, small, and one medium ring gauge, and one cylinder-gauge for each calibre. The cylinder-gauge shall have the same diameter as the large gauge, made of cast iron, and three calibres in length. One hammer weighing two pounds, and having a flat face and a conical point; one searcher, of steel wire, with a handle; one pair of calipers and standard scale; one cold chisel; steel punches.

71. After having been well cleaned, each shot is placed upon a table, and examined to see that its surface is smooth, and that the metal is sound and free from seams, flaws, and blisters. If clusters of cavities or small holes appear on the surface, strike the point of the hammer into them, and ascertain their depth with the searcher. If the depth of the cavity exceeds 0.2 inch, the shot shall be rejected; it shall also be rejected if any attempt is made to conceal defects by plugging or filling holes in any mode whatever.

72. The shot must pass in every direction through the large gauge, and not at all through the small one; the calipers and scale will determine exactly the difference of diameters of the same projectile.

73. The ring and cylinder gauges shall be examined before each inspection, and when found to have enlarged 0.01 of an inch, must be laid aside and marked as unserviceable.

74. The shot are next to be passed through the cylinder-gauge, placed at an inclination of about two inches between the ends, and supported in such a manner as to be easily turned from time to time, to prevent its being worn in furrows. Shot which slide or stick in the cylinder shall be rejected; the latter must be pushed out from the lower end of the cylinder with a wooden rammer.

D. Van Nostrand Publisher. Julius Bien, pr.

75. The next proof of shot is to drop a few taken indiscriminately from the lot under inspection from a height of twenty feet on a solid platform of iron, or roll them down an inclined plane of the same height against a mass of iron; after which they are again examined for defects of metal.

76. The average weight of shot shall be determined by weighing at least three parcels, of from 20 to 50 each, taken indiscriminately from the lot. As many of the lightest shall be weighed separately as the inspecting officer may deem necessary, and all found to fall below the least weight allowed in the annexed table of the dimensions of shot and shells shall be rejected. Shot made of charcoal iron will be stamped with a * or "burr" near the gate.

SHELLS.

77. Shells should be cast on a half-inch hollow spindle, to allow the gas to pass freely from the core; the fuze-hole would then be sufficiently large to admit the gauge for thickness before the shells leave the foundry.

78. Inspecting Instruments.—In addition to the instruments for shot, there will be required calipers with steel points for measuring the thickness of the shell at points on the great circle at right angles with the axis of the fuze-hole; gauges for the thickness at and opposite the fuze-hole; a conical flat steel gauge for the fuze-hole, marked at the point to which it should enter; a pair of strong hand-bellows, with a wooden plug to fit the fuze-hole and the nozzle air-tight. (See Plate.)

INSPECTION.

79. The surface of the shell and its exterior dimensions, form, weight, and strength, are to be examined and tested as in the case of shot, and subject to all the conditions there specified.

80. The greatest care is to be taken to remove every particle of sand or fragment of iron from the interior when they are about to be loaded for service. And the Inspectors of Ordnance at foundries or Navy Yards will satisfy themselves that this has been done before accepting or preparing them for service.

81. The shell is next struck with a hammer, to judge by the ring or sound whether it is free from cracks; and the exterior and interior diameters of the fuze-hole (which should be accurately reamed) are to be verified, and the soundness of the metal about the inside of the fuze-hole ascertained. To determine the thickness of the metal, three points, at least, on the great circle at right angles to the axis of the fuze-hole are to be measured; also one at the fuze-hole and one at the bottom. No shell shall be received which deviates more than one-tenth of an inch from the proper thickness in any part.

82. The shell is next placed in a tub of water, which should be deep enough to completely cover the shell. Air is then forced by the bellows into the shell. If there are any holes in it, air-bubbles will rise on the surface of the water, and the shell shall be rejected.

83. This occasionally occurs from the escape of air from porous spots which do not extend to the interior of the shells. In this case the action of the bellows produces no increase of bubbles, which cease rising as soon as the spots or cavities are filled with water. Porous spots are also detected by their absorbing water and drying slowly when exposed to the air, and shall likewise cause the rejection of the shell.

84. The Inspecting Officers will stamp the shell at one inch from the fuze-hole with their initials, also those of the foundry at which they are cast.

The Inspector or one of his assistants must be present when shot or shell are inspected; and the stamps and marks are always to be retained in the possession of the Inspector.

85. Rejected shells are to be mutilated by chipping a piece out at the fuze-hole.

86. If, upon the inspection of shot or shells, any of them should be found not to conform strictly to these instructions or to the requirements of the contract under which they are offered for reception, the Inspecting Officer is not to receive them; but if, in his opinion, the defects, taken in connection with the general character of the articles, will not impair their efficacy or render them unsafe or hazardous, he may refer to the Chief of the Bureau of Ordnance for his decision, forwarding to him minute and full information on the subject.

87. Shot and shells shall be delivered for inspection at the places specified in the contract, at the expense of the contractor; and those which are rejected shall be immediately removed, also at his expense.

Table of Shot and Shell Gauges.

88.

SHOT.

Dimensions, Weight.				XV. (Cored.)	XIII.	XI.	X.	IX.	8.	32.
Diameter of large gauge for foundries.				14.83	12.83	10.83	9.83	8.83	7.88	6.28
Diameter of small gauge for foundries.				14.77	12.77	10.77	9.77	8.77	7.82	6.22
Mean of gauge for foundries			in.	14.80	12.80	10.80	9.80	8.80	7.85	6.25
Mean weight required of foundries			lbs.	400.	276.	166.	124.	90.	65.	32.5
Least weight allowed foundries			lbs.	—	—	—	—	—	64.5	32.
Diameter of small gauges for service	{	1st class	in.	—	—	—	—	—	7.82	6.22
		2d class	in.	—	—	—	—	—	7.80	6.20

89.

SHELL.

Dimensions, Weight.				XV.	XIII.	XI.	X.	IX.	8.	32.
Diameter of large gauge for foundries.				14.83	12.83	10.87	9.87	8.87	7.88	6.28
Diameter of small gauge for foundries.				14.77	12.77	10.83	9.83	8.83	7.82	6.22
Mean of gauge for foundries				14.80	12.80	10.85	9.85	8.85	7.85	6.25
Thickness.	{	Proper	in.	2.85	2.37	2.	1.80	1.60	1.50	1.25
		Greatest	in.	2.95	2.47	2.1	1.90	1.70	1.60	1.35
		Least	in.	2.75	2.27	1.9	1.70	1.50	1.40	1.15
Diameter of fuze-hole	{	Proper and least		.65	.65	.65	.65	.65	.65	.65
		Greatest		.75	.75	.75	.75	.75	.75	.75
Diameter of large gauge for strapped				14.93	12.93	10.93	9.93	8.98	7.93	6.33
Mean weight required for foundries			lbs.	330.	208.	127.	95.	68.50	50.	25.
Least weight allowed foundries for any one			lbs.	—	—	126.	94.	67.50	49.	24.5
Weight of filled and sabotted			lbs.	352.	216.5	135.5	101.50	73.50	52.75	26.5

For gauges of boat-gun fixed ammunition, see Boat Armament of United States Navy, by Admiral Dahlgren, 2d edition, 1856.

90.

SHRAPNEL.

Dimensions, Weight.				XV.	XI.	X.	IX.	8.	32.	24.	12.
Mean of empty case.	{	Gauge	in.	14.8	10.85	9.85	8.85	7.85	6.25	5.67	4.52
		Thickness	in.	1.25	1.	.87	.75	.69	.60	.55	.45
		Weight	lbs.	178.	76.	57.	38.	29.	15.	11.	6.5
Balls	{	Number		1000.	625.	435.	350.	220.	235. lead	175. lead	80. lead
		Thickness	lbs.	1.	.85	.85	.85	.85	.65	.65	.65
		Weight	lbs.	140.	51.	33.5	27.	17.	14.	10.5	4.75
Sulphur.			lbs.	30.	10.	8.5	7.	5.	2.25	1.5	.75
Bursting charge.			oz.	10.	6.	4.	3.	2.5	1.25	450 grs.	350 grs.
Weight complete.		}	lbs.	358.	141.	101.	75.	52.	32.	24.	12.
Weight sabotted.

91.

DIMENSIONS OF SABOTS AND STRAPS FOR SHELL AND SHRAPNEL.

Dimensions, Weight.				XV.	XIII.	XI.	X.	IX.	8.	32.	24.	12.
Thickness.			in.	5.	4.50	2.75	2.75	2.40	2.	1.50	1.90	1.50
Diameter	{	greatest	in.	14.25	12.25	10.50	9.50	8.60	6.90	6.	5.7	4.60
		least	in.	14.25	12.25	10.50	9.50	8.60	6.80	5.5	5.55	4.40
Depth of saucers.			in.	2.50	2.25	1.80	1.60	1.40	1.20	1.	1.50	1.30
Weights.			lbs.	8.90	5.50	2.70	2.40	1.85	.90	.50	.46	.22
Shell-straps	{	Length	in.	25.75	22.5	17.25	17.25	14.75	13.25	10.25	7.625	6.375
		Width	in.	1.25	1.	.75	.75	.75	.75	.625	.50	.375
		Tin	No.	XXD	XXD	XXD	XXD	IX	IX	IC	IC	IC
Tacks.			No.	20	16	12	12	8	8	8	4	4

92.

GRAPE.

Dimensions, Weight.		XV.	XI.	X.	IX.	8.	32.	24.	12.	Rifle
										20.	12.
Weight of stand	lbs.	—	34.75	26.10	20.4	15.7	8.75
Weight of balls	lbs.	—	89.10	71.70	25.20	37.12	24.80
Number of balls		—	15.	15.	18.	18.	12.
Diameter of balls	in.	—	3.55	3.34	2.80	2.50	2.50
Weight complete	lbs.	—	125.08	98.62	74.10	58.25	33.50

93.

CANISTER.

Dimensions, Weight.				XV.	XI.	X.	IX.	8.	32.	24.	12.
Windage			in.	.25	.25	.25	.25	.25	.25	.15	.15
Height	{	Empty case	in.	15.50	13.50	11.75	10.5	9.75	8.65	5.	3.85
		Finished	in.	1.25	12.	10.5	9.5	8.75	7.75	6.	5.
Case notched, and turned over			in.	.75	.75	.65	.50	.50	.45	4.65	3.52
Thickness of head	{	Top	in.	1.	5/8	5/8	5/8	.75	.50	.35	.3
		Middle	in.	1.	5/8
		Bottom	in.	2.	1.	1.	1.	.75	.50	1.90	1.90
Size of	{	Rod	in.	13/16	1/2	1/2	1/2
		Nut diameter	in.	2.75	1.75	1.75	1.75
		Nut thickness	in.	1.50	1.	1.	1.
		Bale	in.	1/2	3/5	5/8	3/5
Metal and thickness	{	Iron	No.	20.	25.	25.	25.
		Tin	No.	—	—	—	—	XXD	XXD	IC	IC
Balls	{	Number		600.	315.	290.	230.	162.	100.	39.	39.
		Diameter	in.	1.30	1.30	1.30	1.30	1.30	1.30	1.30	1.
		Weight	lbs.	150.	85.	70.	65.	45.	28.	12.5	5.85
Weight finished			lbs.	207.	120.	98.	70.	50.	30.	14.55	7.75

Note.—Bottom of XV-inch canister, of two thicknesses of oak, ash, or beech, crossing each other; put together with wrought-iron nails, clinched; spindle riveting on the bottom through a 3 inches square plate, ¼ thick; cast-iron hexagonal nut, with wrought-iron bale.

For XI, X, and IX-inch, bottom-head one thickness of one-inch oak, ash, or beech; spindle riveting on a plate 1¼ inches wide, by ¼ thick, running across the grain the whole width of bottom, with a rivet at each end of plate.

Top and centre heads of all made of white pine.

Iron cases to be well painted inside with red before filling.

94. Shot of the first class, or which do not exceed 0.18 of an inch windage, are to be entirely black, and those of the second class, having from 0.18 to 0.20 of an inch windage, to be marked partly white. Each class is to be piled and kept separate from every other. Both classes are to be considered and supplied as "serviceable shot;" but are to be stowed separately on board ship, and the returns to the Bureau are to show the number of each, respectively. The number of those having more than 0.20 of an inch windage are to be reported and retained until special orders may be given for their disposition. In case any should be taken as the foundation for piling serviceable shot, they are to be painted entirely white and their number returned as unserviceable.

PILING OF BALLS.

95. To find the number of balls in a pile—Multiply the sum of the three parallel edges by one-third of the number of balls in a triangular face.

In a square pile one of the parallel edges contains but one ball; in a triangular pile two of the edges have but one ball in each. The number of balls in a triangular face is x(x+1) ÷ 2; x being the number in the bottom row. The sum of the three parallel edges in a triangular pile is x+2; in a square pile, 2x+1; in an oblong pile, 3X + 2x-2; X being the length of the top row, and x the width of the bottom tier; or 3m-x+1; m being the length, x the width of the bottom tier.

If a pile consists of two piles joined at a right angle, calculate the contents of one as a common oblong pile, and of the other as a pile of which the three parallel edges are equal.

96.

Table giving the Number of Balls in a Triangular Pile, the Base of which is X.

Value of		Value of		Value of		Value of		Value of
X.	S.	X.	S.	X.	S.	X.	S.	X.	S.
1	1	6	56	11	286	16	816	21	1771
2	4	7	84	12	364	17	969	22	2024
3	10	8	120	13	455	18	1140	23	2300
4	20	9	165	14	560	19	1330	24	2600
5	35	10	220	15	680	20	1540	25	2925

97.

Table giving the Number of Balls contained in a Square Pile, the Base of which is X,
and in a Rectangular Pile, the Sides of which are X and X + N.

Value of X.	Differences		Value of N.											Differences
	2d.	1st.	0.	1.	2.	3.	4.	5.	6.	8.	9.	10.	11.	1st.	2nd.
2 3 4 5	7 9 11 13	9 16 25 36	5 14 30 53	8 20 40 30	11 26 50 85	14 32 60 100	17 38 70 115	20 44 80 130	23 50 90 145	26 56 100 160	29 62 110 175	32 68 120 190	35 74 130 205	3 6 10 15	3 4 5 6
6 7 8 9 10	15 17 19 21 23	49 64 81 100 121	91 140 204 285 385	112 168 240 330 440	133 196 276 375 495	154 224 312 420 550	175 552 348 465 605	196 280 384 510 660	217 308 420 555 715	238 336 456 100 770	259 364 492 645 825	280 392 528 690 880	301 420 564 735 935	21 28 36 45 55	7 8 9 10 11
16 17 18 19 20	35 37 39 41 43	286 324 361 400 441	1496 1785 2109 2470 2870	1632 1988 2280 2660 3080	1768 2091 2451 2850 3290	1904 2244 2622 3040 3500	2040 2397 2793 3239 3710	2126 2550 2964 3420 3920	2312 2703 3135 3610 4130	2448 2556 3806 3800 4340	2584 3009 3477 3990 4550	2720 3162 3648 4180 4760	2856 3315 3819 4370 4970	136 154 111 190 210	17 18 19 20 21
21 22 23 24 25	45 47 49 51 53	484 529 576 625 676	3311 3795 4325 4900 8525	3542 4048 4600 5200 5850	3773 4301 4876 5500 6175	4004 4554 5152 5800 6500	4235 4807 5428 6100 6825	4466 5060 5704 6400 7150	4697 5313 3980 6700 7475	4928 5566 6256 7000 7800	5159 5819 6532 7300 8125	5390 6072 6803 7600 8450	5621 6325 7084 7900 8775	231 253 276 300 325	22 23 24 25 26

The number contained in a square pile is found in the column opposite the number X.

In a rectangular pile let the smaller side be 19 = X, the longer side be 26 = X + N. Then N = 7. Under 7 and opposite 19 we have 3,800. This table may be indefinitely extended by the aid of the columns of differences.

PRESERVATION OF SHOT AND EMPTY SHELL.

98. All round shot and shell are to be cleaned from rust and covered with a thin lacquer of such composition as may be directed by the Bureau when they are first received and when they are restowed.

99. For the present the following colors are established when put on board ship: All shot, black; shell, red; shrapnel, white; length of fuze stencilled on the shell. Special kinds of shell, as may be directed by Bureau. (Crane's shell, yellow; Pevey, blue.)

100. Empty shell, whether in store or in transportation, shall be most carefully protected from damp, and are to have the fuze-bouching coated with such composition as may be directed, and be stopped by a plug of very soft wood, well coated with a mixture of oil and tallow, screwed into them. The ends of the plugs should not be sawed off even with the shell, but left square and project sufficiently to allow them to be unscrewed by means of a wrench, and whenever these plugs are removed for the purpose of fitting the shells for service, they are not to be thrown away but preserved for future use.

They are to be piled with the fuze-holes down, and free from contact; under cover when practicable, but with free ventilation.

101. Platforms of masonry, or of condemned shot, are to be prepared to pile shot and shell upon, and are not to be wider, if space can be found than to stow fourteen 32-pdr. shot, or not exceeding eight feet in width. Square piles are to be preferred where there is room, but where this may be deficient, the piles may be extended in length.

102. Shot and shell, after having been piled, are to be so far examined in the first week of June in each year as to ascertain if they require to be cleaned, relacquered, and repiled to secure their proper preservation; and their condition reported to the Bureau, that if any work upon them is necessary it may be finished during the warm months of the year, when the lacquer can be best applied.

103. Whenever shot or shell are to receive lacquer care must be taken that the quantity applied does not increase the diameter more than is indispensably necessary, and in no case above the established high gauge. Old lacquer and rust should be removed by scraping, as far as can be conveniently done before a new coating is applied. For use at the Navy Yards, a milling machine performs this very expeditiously. Neither hammering nor heating is to be resorted to for this purpose.

Note.—After numerous experiments upon different lacquers employed for the preservation of shot and shell from rust, the French have abandoned all of them.

The shot and shell are simply piled, under sheds when practicable, or in the open air, and when put on board ship cleaned of rust and rubbed over with whale oil—the same means adopted every three months during the cruise.

PREPARATION OF SHELL FOR SERVICE.

104. The fuzes for shell will be prepared at the Laboratory in the Ordnance Yard at Washington, and distributed to other Navy Yards as they may be required. All fuzes taken from shell, or returned from ships which have been more than one year in service, are to be sent to the laboratory to be refitted. Fuzes of over two years date of manufacture, are not to be issued for service, but returned to the laboratory.

105. The charges of powder for spherical shell are to be as follows:

	XV-inch	XI-inch	X-inch	IX-inch	8-inch	32-Pdr.	Boat and Field Howitzers.
							24-pdr.	12-pdr.
	Lbs.	Lbs.	Lbs.	Lbs.	Lbs.	Lbs.	Lbs.	Lbs.
Bursting or Service Charge	13	6.00	4.00	3.00	1.85	0.90	1.0	0.5
Blowing Charge	1.0	0.25	0.25	0.25	0.25	0.25

Note.—The weight of charges for shells will vary slightly from those given in the table according to the size of the grain and density of the powder.

106. All empty shell, whether in store or in transportation, shall be most carefully protected from dampness, and their fuze-holes invariably closed with wooden plugs. Whenever these plugs are removed for the purpose of fitting the shells for service, they are not to be thrown away, but preserved for future use. If by any accident the shell should be damp in the interior, they are to be heated and dried, on the grillage prepared for that purpose.

107. The number of shell to be kept fitted at the Navy Yards will be determined by special directions from the Bureau.

In fitting shell to receive the bouching, great carelessness has been observed. The hole should be tapped with a full thread, and the proper shoulder left at the bottom to prevent the bouching from being driven in by the shock of firing and causing premature explosion.

108. All shell shall be filled with musket-powder of the highest initial velocity. The shell must be filled, and the powder well shaken down, leaving only room for the insertion of the fuze. A wooden plug the size of the lower part of the fuze will always determine this. The very common, but slovenly, practice of filling the shell, and then pouring out a quantity sufficient to allow the fuze to be inserted, is expressly prohibited. Shell have also been returned with the powder in the vicinity of the fuze compressed into a solid mass, owing to the fact that sufficient room had not been left for its insertion. No shell shall be fuzed unless it has been filled.

109. The date when shell are fuzed or filled, as well as that on which any of these arrangements are changed, or the shell are examined before issue to vessels, together with the initials of the officer superintending these operations, should be legibly written and pasted on the shell, or stencilled on the box.

110. The Ordnance Officer, or the Gunner of the Yard, is to see the shell supplied to all vessels properly conveyed on board, superintend the stowage, and furnish the Commanding Officer with a statement showing the number of each description of shell and fuze, and a plan of their stowage.

111. The condition of the shell, and especially of their fuzes, is to be frequently and carefully examined into, taking out a fuze occasionally so as to detect any injury which may arise from moisture, and to have such as may be found damaged replaced by the spare fuzes.

Boat shell and their spare fuzes are also to undergo a similar examination.

Shell have been sometimes returned with their fuzes entirely destroyed by moisture!!

112. It has been found recently, on drawing the charge of a 12-pounder howitzer in one of the small gunboats, that in cutting its fuze (Bormann) the incision had been made directly into the magazine.

Had the gun been fired, the explosion of the shrapnell must have occurred at the muzzle of the gun.

There is no doubt such errors will often account for the supposed defects of the fuze.

The attention of officers is therefore required to this subject; and, in making reports of defective ammunition, samples should be forwarded to Washington for examination.

It is of the gravest importance, not only because it involves the failure of the shell to act properly upon the object of fire, but may also endanger the lives of our own men.

113. Whenever it is expedient or necessary to examine the fuzes and loading of shell which have been already prepared, great care must be observed in removing the fuze. It should never be done in the shell-room.

114. The fuze-stock may generally be safely unscrewed with the fuze-wrench, taking care, in the first place, to strike the side of the shell gently with a wooden mallet, to detach the powder from the fuze, to work very slowly, and not to endeavor to overcome any unusual resistance.

115. Whenever it shall be necessary to load and fuze shell on board ship—a properly secured place being first prepared, as directed by the Captain, not in the shell-room and as far from the magazine as convenient—the shell, being strapped and sabotted, are to be examined to see that they are clean, both inside and out, and thoroughly dry. The greatest care is to be taken to remove every particle of sand or fragment of iron from the interior. The prescribed charge of powder is next to be poured into them through a proper funnel; care is to be taken that the end of the funnel passes below the screw-thread in the tap or bouching, to prevent any grains of powder entering it; any grains of it which may remain sticking to the thread of the bouching are to be brushed away carefully, and then, after putting a light coat of lacquer for small arms, or sperm oil, on this thread and on that of the fuze, the latter is to be screwed in carefully with the fuze-wrench. The lacquer should be of the consistency of cream, and when from evaporation, it becomes too stiff, should be thinned by adding more spirits of turpentine.

116. In emptying shell they are to be handled carefully and placed on a bench with a hole in it to receive and support the inverted shell. A wooden vessel placed below will receive the powder. The powder which has been removed from shell shall only be used for filling shell, as it always contains a small quantity of grit, which renders it unfit for general service. Should the powder have become caked, so as not to be easily removed from the shell, it is to be drowned and removed by washing out the shell. A handful of small iron shot put in the shell will facilitate this operation.

117. Loaded shell are to be painted red and placed in boxes or bags marked with a red cross, which boxes are to have the lengths of fuze painted on them in black. Shrapnel shell and the tops of their boxes shall be painted white, with the length of fuze stencilled on them in black. They are to be stowed in shell-houses prepared for that purpose. Loaded shell, whether in or out of their boxes, must be handled carefully. Shell-bags will be preserved, accounted for by the Gunner, and returned.

118. The greatest precaution must be taken in handling loaded shells fitted with percussion-fuzes. When returned from ships they must not be taken into the shell-houses until after the fuzes shall have been removed and the shell plugged.

119. Shell-houses, and the general condition of the shell they contain, are to be examined as often as once a fortnight by the Ordnance Officer, and every precaution taken to keep them as dry as possible.

120. The shell for boat guns are to be stowed in "the shell-houses" on shore, and "shell-rooms" on board of vessels, in their proper boxes.

121. One-fourth of the whole number of spare fuzes allowed for the great guns is to be for 5 seconds of time; one-fourth for 10 seconds; one-fourth for 15 seconds; one-fourth assorted of 3, 5, 7, and 20 seconds.

122. All the spherical shell, however, put on board ship, filled and fitted for immediate use, are to be provided with none other than the 5-second fuze. No fuze is, under any circumstances, to be put in shell which are not filled.

123. For rifled cannon the shell shall be fitted with one-half percussion, one-half time fuze. Parrott's shell will have bouching, or "adapting" rings for the naval time fuze. The new form of adapter, with a shoulder and washer beneath it, shall alone be used.

124. At ranges exceeding 1,400 yards the 10 or 15-second fuzes, according to such excess, are to be substituted for the 5-second fuze, by removing one and putting in the other; or, if preferred, those fuzes may be applied to shell which are not already fitted. The 5-second fuze is to be regarded as the general working fuze, and hence the reason the filled shell are to be fitted with it, as mentioned above. (See TABLE OF RANGES for proper lengths of fuze for all distances.)

125. The different kinds of fuzes shall be made up in separate packages, distinctly marked with the kind and length of fuze, and their use carefully explained to the Executive Officer and Gunner by the Inspector of Ordnance.

126. In consequence of numerous reports received from vessels in service of the inefficiency of certain fuzes, commanders of vessels are required to observe carefully the action and result of all fuzes, and report in detail to the Bureau of Ordnance whenever opportunities may occur, particularly specifying the number and kind fired, elevation of gun, range, premature explosions, failures to explode, and satisfactory action. Also, whether the fire was direct or ricochet.

127.

Exterior Dimensions, in Inches, for Shell-Boxes.

For XV-inch shell, 18 × 18 by 20 high.
For XI-inch shell, 12.75 × 12.75 by 14.5 high.
For X-inch shell, 11.65 × 11.65 by 13.9 high.
For IX-inch shell, 10.63 × 10.63 by 12.9 high.
For 8-inch shell, 10.20 × 10.10 by 12.2 high.
For 32-pounder shell, 8.60 × 8.50 by 10.2 high.

128.

Areas occupied by one Tier of Shell-Boxes.

XI-inch		X-inch		IX-inch		8-inch		32 Pounder.
No.	Ft. In.	No.	Ft. In.	No.	Ft. In.	No.	Ft. In.	No.	Ft. In.
72 52	15.5½ × 5.8½ 14.4 × 4.6½	75 56	15.2 × 5.3½ 14.2 × 4.1½	102 80	15.8¼ × 5.9¼ 14.9¼ × 4.9½	108 85	16 × 6 15 × 5	176 140	16 × 6 15 × 5

GUNPOWDER.

STOWAGE, PRESERVATION, HANDLING, AND CHARGES.

129. The Bureau having adopted a new system of granulating Navy powder, the different classes will in future be known and designated as Rifle, Cannon, and Musket.

Gunpowder intended for ordinary use in cannon is to have sufficient strength to give a 6-pounder shot the under-mentioned Initial Velocities, determinable by the gun-pendulum of the Ordnance Yard at Washington.

130. The size of the grains is determined by sieves, made by piercing round holes in thin plates of brass. These sieves are five in number, the holes being of the following diameters, viz.:

No. 1, .3 of an inch No. 2, .15 of an inch	}	Initial Velocity required, 1450 feet +50-50, for Rifle.
No. 2, .15 of an inch No. 3, .10 of an inch	}	Initial Velocity required, 1500 feet +50-50, for Cannon.
No. 4, .06 of an inch No. 5, .02 of an inch	}	Initial Velocity required, 1550 feet +50-50, for Musket.

Rifle powder is used in the Parrott rifles of 8-inch, 100-pounder, and 60-pounder. Navy cannon powder in all other rifles and all smooth-bores.

131. Size of the grain is required to conform to the following:

Pass through No. 1 Remain on No. 2	}	all Rifle.
Pass through No. 2 Remain on No. 3	}	all Cannon.
Pass through No. 4 Remain on No. 5	}	all Musket.

Ten per cent. variation tolerated.

132. Gravimetric Density, is the weight of a given measured quantity: it is usually expressed by the weight of a cubic foot in ounces.

This cannot be relied on for the true density, as the size and shape of the grain may make the denser powder seem the lighter.

Cannon powder should have a gravimetric density of about 875 oz., and not exceeding 900 oz., to the cubic foot. (It actually varies with different makers from 875 to 975.)

133. Specific Gravity.—The specific gravity of gunpowder is between 1.70 and 1.75.

All the powder of any lot being made of the same mill-cake, the specific gravities are equal although the gravimetric densities may vary.

134. Powder for small arms, or musket powder, should all pass through No. 4, none through No. 5, and average from 2,000 to 2,500 kernels in tea grains Troy.

All powder should be well glazed; for small arms more highly than for cannon.

135. The system of granulation adopted by the Army differs from that of the Navy, as follows:

	All Through—	All On—
Mammoth	0.9 in.	0.6 in.
Cannon	0.35	0.25
Mortar	0.10	0.6
Musket	0.06	0.3

It will be seen by this Table that under the Army nomenclature, Navy Rifle nearly corresponds to Army Cannon; that the Army Mortar is the nearest equivalent to Navy Cannon, but with much more fine grain, as it is what passes through the cannon-sieve, but remains on the musket-sieve; and that the Navy Musket has the same size for the larger grain, but contains more small grain than the Army.

In exchanging powder with the Army, it is necessary to attend to these distinctions.

136. Powder-houses or magazines on shore are to be inspected by the Ordnance Officers at least once in every week, and every precaution taken to guard them against danger of explosion, and to preserve the powder dry and in good condition.

137. Powder-barrels in magazines, where there are no racks, should be placed on their sides, with their marked ends towards the alleys, three tiers high, or four tiers, if necessary, with small skids on the floor and between the several tiers of barrels, using chocks at intervals on the lower skids to prevent the barrels from rolling. If it can be avoided, fixed ammunition should not be put in the same magazine with powder in barrels.

138. If it is necessary to pile the barrels more than four tiers high, the upper tiers should be supported by a frame resting on the floor; or the barrels may be placed on their heads, with boards between the tiers.

There should be an unencumbered space of 6 or 8 feet square at the doors of the magazine.

139. Whenever practicable, the barrels should be arranged in double rows, with a passage-way between the rows, so that the marks on each barrel may be seen at a glance, and any barrel easily reached.

140. Besides being recorded in the magazine-book, each lot of powder should be inscribed on a ticket attached to the lot showing the entries and the issues.

141. Magazines should be opened and aired in clear, dry weather, the ventilators kept free, and no shrubbery or trees allowed to grow so near as to shade the building from the sun.

142. The moisture of a magazine may be absorbed by chloride of lime, or charcoal, suspended in an open box under the arch, and renewed from time to time. The use of quicklime is dangerous, and forbidden.

143. When powder is handled in powder-houses on shore, either for the purpose of inspection or preparation for delivery to ships, the baize-cloth is to be spread, and the people, before entering the magazine, must divest themselves of every metal implement, empty their pockets, that nothing likely to produce fire may escape detection, and put on the magazine dresses and slippers. The barrels must be opened only on the floor-cloth, and no metallic setter used in driving either copper or wooden hoops.

Powder-barrels should never be opened except when required for use, as grains of powder falling between the staves would prevent their being tightened. Samples must be taken from the bung.

144. The attention of the Inspectors of Ordnance and Commanders of vessels is called to the Regulations regarding the stowage and service of powder and loaded shells in Magazines and Shell-rooms, ashore and afloat, and to the precautions which must be observed by every one who enters, or approaches for the purpose of entering, any Magazine or Shell-room.

The former Regulations are modified so far as to dispense entirely with the use of slippers made of either India-rubber or woollen; and in lieu thereof, slippers made wholly of buckskin or cotton canvas will be used in future. In hot climates, or in warm weather generally, the naked feet are preferred.

The terrible effect of the explosion of a Magazine or Shell-room, ashore or on board ship, can only be imagined. To avert it, by every human precaution, is an imperative duty with every one. The Bureau therefore directs that the Inspectors of Ordnance on shore and the Commanders of all vessels afloat will cause the existing Powder Regulations to be read, and copies placed within the reach of every officer and man connected in the remotest degree with the service of the Magazine and Shell-rooms; and no officer or other person is to be continued in such service who cannot within a reasonable time answer clearly and fully any questions relating to the requirements of existing Powder Regulations as contained in these "Ordnance Instructions."

145. The powder in barrels should be turned from time to time, at least as often as every three months, and, being arranged as mentioned above, the oldest powder will be at all times accessible for first delivery without disturbing that of more recent manufacture.

>146. When powder is sent on board any vessel at the Yard, an Ordnance Officer or the Gunner is to see it properly stowed, and the Ordnance Officer is to hand to the Captain of the vessel a statement showing the quantity of powder, number and capacity of tanks, kind of charges contained in each, with the initial velocity, maker, and date of reception, with a list of small-arm and boat ammunition, fireworks, filled and other shells and projectiles, together with all the information directed by the three articles immediately following, with such remarks as he may deem proper to secure better precaution or more convenient arrangement, with a request that the memorandum, or a copy of it, may be delivered to the Ordnance Officer at the Yard where the vessel is refitted or laid up at the end of the cruise.

147. When cartridges are filled for issue to any vessel, the powder should be selected, as far as practicable, from deliveries made by the same person, and at the same time or date; and the tanks in which they are stowed must be marked with white paint on the upper sides, with the same marks as the barrels from which the powder was taken, giving the date of manufacture and the maker's name.

148. Great irregularities having been observed in the weights of cartridges supplied from different stations, it is ordered that at least ten measures shall be weighed at each filling, and allowance made for different densities. (See [Art. 171.])

149. Whenever powder is returned into the powder-houses from vessels, and the powder emptied from the cartridges, care must be taken to have the barrels or other vessels in which the powder may be placed marked in the same manner and registered in the Magazine Ledger, so that the maker's name and date of manufacture of all powder may be correctly known and carefully preserved for reference.

150. The names of vessels from which powder is received, the length of time which the powder has been on board, and the station on which the vessel has been employed, should also be noted and reported by the Ordnance Officer, that reference may be had to the notes in case it should be desired in subsequent examinations of the powder.

151. In some instances where powder has been condemned by survey, it has been directed to be thrown overboard. This should never be done; the nitre contained, which forms three-fourths (¾) of the powder, is still perfectly good, and can be made serviceable. In future, condemned powder is always to be returned to the United States.

152. The Ordnance Officers, when they supply vessels with powder, or remove any from them, must report to the Bureau by the earliest opportunity all the information which is required to be noted by Articles 147, 149, 150, immediately preceding; and when powder is received from vessels returning from cruises, or after it has been long embarked, they are to forward to the Ordnance Yard, Washington, a sample of two pounds and one-fourth, properly labelled, for every five hundred pounds landed, selected so as to show fair average samples of the whole, in order that its strength may be ascertained by the pendulum.

153. In case of necessity, powder for saluting may be purchased abroad in order to preserve a supply of our own proof powder for battle.

154. When a vessel is about to leave a foreign station and return directly to the United States, and other vessels belonging to the Navy are left on the station without a full supply of powder, the vessel which is about to leave may be directed to transfer to those remaining on the station any excess of powder that may be on board beyond fifty rounds.

155. Should it become necessary to use powder for service charges which has not been regularly inspected and proved in the manner required by regulations, such tests of it must be made as circumstances will admit.

The ranges given by it may be compared with those of service powder of known good quality under the same circumstances. If deficient in strength, the quantity of the charges should be increased until the ranges are equalized, in order that the sight-bars may still indicate the proper elevations for each charge and distance.

156. It is directed that vessels of war shall always receive their powder and loaded shells in the stream; unless, upon some great emergency, the nature of which shall be reported to the Bureau, it is deemed essential to put them on board at the Navy Yard.

157. When receiving or landing powder, the red flag is to be always hoisted at the fore, and all proper precautions taken to guard against accidents from fires and lights. The tanks should be passed through the ports most convenient to the magazines, and landed on mats, to prevent injury.

The red flag is always to be hoisted at the powder-houses when they are opened, and kept flying until they are closed.

158. When avoidable, gunpowder is not to be sent from vessels to powder-houses, nor from powder-houses to vessels, in wet weather, nor when there is a probability of wetting the barrels or cases; and the packages must be conveyed in covered boats or wagons showing a red flag.

159. The wharf or landing-place must be spread with old canvas, so that the barrels or cases may not come in contact with and convey sand or gravel to the powder-house. The barrels must not be rolled, but carried in slings to the trucks running on tramways of either wood or bronze, into the magazine.

160. The service charges for the different calibres and classes of naval smooth-bore guns now used in the Navy are as follows, and the cartridges are to be filled accordingly, viz.:

Service Charges for Naval Guns.

Ordnance.		Charges of Navy Powder.			Diameter of Cartridge-Gauge.	Saluting Charges, No. 50.
Calibre.	Weight.	For distant firing, 0.1	For ordinary firing, 0.6	For near firing or two projectiles, 0.3
		lbs.	lbs.	lbs.	Cylindrical.	lbs.
X-inch or 130-pounder	16,000 lbs.	30.	18.	15.	9.00 inches.	6.
64-pounder	106 cwt.	16.	12.	8.	7.00 inches.	4.
32-pounder	61 cwt.	10.	8.	6.	5.50 inches.	4.
32 do.	57 cwt.	9.	8.	6.	5.50 inches.	4.
32 do.	51 cwt.	8.	7.	5.	5.50 inches.	4.
32 do.	46 cwt.	7	7.	5.	5.50 inches.	4.
32 do.	42 cwt.	6.	6.	4.	5.50 inches.	4.
32 do.	33 cwt.	4.5	4.5	4.	5.50 inches.	4.
32 do.	27 cwt.	4.	4.	3.	5.50 inches.	3.
Shell-guns				For near firing.	Conical.
XV-inch	42,000 lbs.	50.	35.	35.
XI-inch	15,700 lbs.	20.	15.	15.	11 × 5.5 × 11	7.
X-inch	12,000 lbs.	15.	12.5	12.5	10 × 5. × 10	6.
IX-inch	9,000 lbs.	13.	10.	10.	9 × 4.5 × 9	5.
8-inch	6,500 lbs.	7.	7.	7.	8 × 5. × 8	4.
32-pounder	4,500 lbs.	6.	6.	6.
					Cylindrical.
8-inch	63 cwt.	9.	8.	6.	5.50	4.
8-inch	55 cwt.	7.	7.	6.	5.50	4.

N.B.—Two projectiles are not to be fired from any gun at the same time, except at objects within 200 yards' distance, and only when the advantages at the moment may be deemed by the Captain sufficient to justify the risk of injuring the guns and their equipments by the extra strain to which they will be exposed.

With the 15-inch guns at close quarters against iron-clads, 60 lbs. and a solid shot may be used for 20 rounds. So also with the 11-inch, 30 lbs. and a solid shot. With all the other guns, under like circumstances, and where penetration is desired, the distant firing charges should be substituted for the near firing.

Of the service charges, one-tenth shall be for distant firing, six-tenths for ordinary firing, three-tenths for near firing, or for two projectiles. Saluting charges to be of under-proof powder.

The calibre and class of guns for which the cartridges are intended must be distinctly marked near the top of the lid end of the tanks.

161.

Table of Charges for Navy Rifle Guns.

Gun.	Ordnance.			Charge of Powder.
	Calibre.	Diameter of Bore.	Weight.	Weight.	Kind.	Diameter of Cartridge-Gauge.
	Pounder.	Inches.	Lbs.	Lbs.		Inches.
Parrott	100	6.40	9,700	8.	Rifle.	5.50
Do.	60	5.30	5,400	6.	Rifle.	4.60
Do.	30	4.20	3,550	3.25	Cannon.	3.70
Do.	20	3.67	1,750	2.	Cannon.	3.25
Dahlgren	20	4.00	1,340	2.	Cannon.
Do.	12	3.40	880	1.	Cannon.

162.

Powder-Tanks.

Capacity of Tank for Powder in Grain.	Exterior Dimensions.		Weight, when empty.	Approximate Weight, when filled with Cylinders.
	Height in inches including Lid and Handle.	Sides in inches.
200 pounds	22 1/4	16 1/2 × 16 1/2	67 1/2 pounds.	218 Pounds.
150 pounds	22 1/8	15 × 15	59 1/2 pounds.	170 to 180 lbs.
100 pounds	20 1/2	13 × 13
50 pounds	16 3/4	10 1/4 × 10 1/4

163.

Accommodation afforded by Powder-Tanks of different Sizes
for Cartridges of various Kinds when closely packed.

Capacity of Tank for Powder in Grain.	Will Stow Cartridges as follows:
Denomination.	lbs. 20	lbs. 16	lbs. 15	lbs. 12.5	lbs. 10	lbs. 9	lbs. 8	lbs. 7	lbs. 6	lbs. 5	lbs. 4.5	lbs. 4	lbs. 3.25	lbs. 3	lbs. 2	lbs. 1.85	lbs. 1
200 pounds.	9	11	12	14	18	20	22	25	30	36	40	45	52	60	95	100	190
150 pounds.	6	8	9	10	13	15	16	20	24	27	30	36	40	45	71	72	145
100 pounds.	4	5	6	7	9	10	11	13	16	18	20	24	27	31	46	48	95
50 pounds.	2	2	2	3	4	4	5	6	7	9	10	11	13	15	21	23	46
Powder-barrel.	4	6	7	8	10	11	12	14	15	—	—	26	—	35	52	55	108

FIXED AMMUNITION FOR BOAT GUNS AND SMALL ARMS.

164. The charges for "boat and field howitzers" are—

	lbs.
For the 24-pounder of 1,310 lbs.	2.00
For the medium 12-pounder of 760 lbs.	1.00
For the light 12-pounder of 430 lbs.	0.625

165.

Dimensions of Boxes for Boat Ammunition.

PROJECTILES WITH CHARGE OF POWDER FOR HOWITZER ATTACHED, NOT TO BE STOWED IN THE MAGAZINE.

Calibre of Boat Howitzer.	Kind of Projectile.	Number of Projectiles Box contains.	Dimension of Boxes, in Inches.	Weight, in Pounds.
				Empty.	Filled.
24-Pdr.	Shrapnel	9	22 × 20.75 by 13.75 high	35 1/3	270 1/2
24-Pdr.	Canister	9	22 × 20.75 by 13.50 high	36 1/3	217 5/6
12-pdr. heavy	Shrapnel	9	18.75 × 17.75 by 11.13 high	22 7/8	140 1/2
12-pdr. heavy	Canister	9	18.75 × 17.75 by 12.25 high	25 1/2	114 3/4

166. The cartridges for small arms are to contain the following quantities of powder:

For muskets	70 grains, Troy.
For muskets (marine)	60 grains, Troy.
For pistols	30 grains, Troy.
For revolvers	18 grains, Troy.

The ball-cartridges for rifles and rifled muskets are to be made with a single Minié ball.

167.

Exterior Dimensions and Contents of Boxes

FOR SMALL-ARM AMMUNITION AND FIREWORKS.

Articles.	Exterior Dimensions.			Each Box Contains.	Remarks.
	Length.	Width.	Depth.
	Inches.	Inches.	Inches.
Musket-ball cartridges	12 1/2	8 1/4	8 1/4	500
Musket blank cartridges	9 5/8	7 3/4	8 1/2	500
Carbine rifle-ball cartridges	14 1/2	9 1/4	7 3/8	1000
Pistol-ball cartridges	13 3/4	6 3/4	7 1/4	1000
Blue-lights	20 1/2	13	6 7/8	30
False lights	20 1/2	13	6 7/8	30
Port-fires	19 3/4	10 1/4	10 1/4	100	First size.
Port-fires	19 3/4	10 1/4	6 1/4	50	Second size.
Signal rockets	15 1/4	9 1/2	8 1/4	30
Percussion-caps	11 3/4	9 1/4	7 3/8	6300

N.B.—There is a variation in the dimensions of the above boxes, as made, of 1/3 of an inch, on an average, in their exteriors.

168. Percussion-caps and bullets for small arms will be supplied from the Ordnance Yard at Washington.

169. The boxes in which cartridges for small arms, caps, primers, etc., are packed for distribution to vessels, are to be marked with the number they contain, and the kind of arm for which they are intended. At the expiration of the cruise they must be carefully returned into store, and the Gunner will be held peculiarly responsible for their loss.

170. Standard powder-measures for filling cartridges for great guns will be made at the Ordnance Yard, Washington, and distributed as they may be required for the use of vessels and shore magazines. As the gravimetric density of powder varies from 860 to 940, the weight of the contents of ten measures should be ascertained for each lot, and allowance made accordingly before filling the cartridges.

171. In taking the weights, the powder is to be scooped up from the filling-chest with the measure until it is heaped, tapped twice moderately on the sides with the palms of the hands, and then struck with a wooden straight-edge. If the weight differs materially from that marked on the measure, a small compensating measure should be used to supply the deficiency or remove the excess.

CANNON-PRIMERS.

172. These are of two kinds, percussion and friction. Each percussion-primer is composed of a quill tube capped by an explosive wafer. The quills used for this purpose are first inspected by passing them through a gauge rather smaller than the vent.

The tube is filled with fine-grained powder.

The wafer is composed of a cap of cartridge-paper, enclosing a layer of fulminate of mercury combined with a small quantity of mealed powder. When pressed and perfectly dry, the wafer is coated with uncolored shellac, to preserve it from dampness.

173. Primers are to be kept in tin boxes containing fifty each, the lids of which are luted with shellac to exclude moisture until wanted for immediate use. These boxes are intended to fit in and form a lining to the primer-boxes which slip on the waist-belts worn by Captains of guns. For purposes of exercise no more of these boxes should be opened than are required; but for action a full box should be delivered to each Captain and 2d Captain of a gun.

174. A friction-primer consists of a tube charged with gunpowder, to the top of which is fastened a spur containing friction-powder, which is exploded by means of a slider pulled out by a lanyard. It is intended for use in case the lock should be out of order, or the other primers fail from any unforeseen cause. Friction-primers are packed in tin boxes in the same manner as percussion-primers. They are obtained from the Army as required.

175. Filled boxes of primers are kept in close laboratory cases, for which stowage must be provided in the general store-room of the ship, or other safe place.[1] They are on no account to be placed in the magazine, and the boxes must be so labelled before being put on board ship.

176. When primers have been returned from cruising ships, or have remained in store for one or more years, they must be tested by firing five per cent. of the number, and not issued again without special orders.

177. Damaged fuzes, primers, caps, and tubes, are always to be returned to the Ordnance Yard at Washington, in the condition in which they were received on the return of the ship.

178. The boxes containing metallic cartridges for breech-loading arms require the same care as percussion-caps, and are to be labelled, "On no account to be placed in the magazine."

179. Percussion-Caps for muskets, carbines, and pistols are made in the laboratory at the Washington Navy Yard. They are put up in small packages of water-proof paper, labelled with the number contained in the package and the date of fabrication, and stowed in tin cases containing 350 caps each.

180. Laboratory boxes, in which these are packed, are of the following dimensions: 11 3/4 × 9 1/4 × 7 3/8 inches, and will contain 6,300 percussion-caps each. These boxes are to be labelled, "On no account to be placed in the magazine." Stowage is provided for them in the general store-room.

CARTRIDGE-BAGS.

181. The material of which cartridge-bags are made is woven expressly for the purpose, and furnished by the Bureau of Ordnance as required. The color is white, and the calibre of the gun and the weight of the charge must be stencilled on the bag in figures two and a half (2 1/2) inches long. When procured of necessity elsewhere, the stuff should be chosen of wool, entirely free from any mixture of thread or cotton, and of sufficiently close texture to prevent the finer particles of powder from sifting through. Wildbore, rattinet, merino, and bombazette are named as proper materials for cartridge-bags; of these the thinnest stuff, not twilled, but having the requisite strength and closeness of texture, is the best.

182. Making Cartridge-Bags.—Cartridge-bags for cylindrical chambers are made of a rectangle to form the cylinder, and a circular piece to form the bottom. The flat patterns, by which the cartridge-bags for the 8-inch and 32-pounder guns are cut, are, consequently, to be made rectangular for the cylindrical part of the bag, and circular for the bottom. The length of the rectangle is equal to the development of the cylinder, together with the allowance for seam; and its width, to the whole length of the bag before sewing, including the allowance for seam and tie.

Special patterns are furnished for those of XV-in., XI-in., X-in., IX-in., 8-inch of 6,500 lbs., and 32-pounder of 4,500 lbs. shell-guns, all of which have gomer chambers.

183.

Dimensions of Flat Patterns for Cutting out Cartridge-Bags.

TO BE MADE OF PINE FOR THE 8-INCH AND 32-PDR. GUNS, AND OF METAL PLATES FOR THE "GOMER" CHAMBERS OF OTHER GUNS.[2]

Dimensions.		10-inch, or 130-pounder.			64-pdr. Gun of 106 cwt. 8-in. Rifle.			100-pounder Rifle, 32-pounder Gun, and 8-inch Shell-Guns, having Chambers Of 32-pounder Calibre.
Charges	lbs.	30	18	15	16	12	8	10	9	8	7	6	5	4.5	4	3
Width of rectangle (length of bag cut), including tie and four-tenths of an inch for seam.	in.	20	15.2	14	18.7	15.7	12.7	16.6	14.6	18.0	12.6	11.6	10.6	10.1	9.6	8.6
		Inches.			Inches.			Inches.
Length of rectangle (cylinder developed), including eight-tenths of an inch for seam.		29.01			23.80			18.10
Radius of circular pattern of bottom, including four-tenths of an inch for seam.		4.9			3.60			2.95
Diameters of cylindrical formers for inspection of cartridge-bags.		9.00			7.00			5.50
Additional length for one pound of powder.		0.40			0.80			1.22

184.

Details of Cartridge-Bags.

SHELL-GUNS WITH CONICAL CHAMBERS.

Calibre of Gun.		XV-in.			XI-in.		X-in.		IX-in.		8-in. of 6500.	32-pr. of 4500.
Charge of powder	lbs.	35.	50.	60.	20.	15.	15.	12.5	13.	10.	7.	6.
Diameter of cartridge.
large end		13.5	13.5	13.5	9.85	9.85	9.	9.	8.13	8.13	7.25	6.
small end		—	—	—	5.50	5.50	5.	5.	4.50	4.50	4.	8.5
Width of stuff required to cut bag.	in.	24.	28.	30.	22.	20.	20.	20.	18.	18.	24.	22.
Whole length of bag cut, including tie and seam.	in.	21.5	25.5	27.5	10.	17.5	18.5	17.75	16.5	15.5	12.0	11.0
Length of filled cartridge.	in.	12.	15.5	18.	12.	10.5	10.	9.	11.5	10.5	7.5	9.5
Length of filled cartridge.	in.	12.	15.5	18.	12.	10.5	10.	9.	11.5	10.5	7.5	9.5
Additional length for one pound of powder.	in.
Quantity of stuff required to cut one hundred bags.	yds.	122.	122.	122.	92.	92.	86.	86.	78.	78.	30.	30.

In cutting, the length of the rectangle should be taken in the direction of the length of the stuff, as it does not stretch in that direction, and the material should be chosen, as nearly as possible, of the width required for the length of the bags, to save waste in cutting.

The bags are to be sewed with worsted yarn, with not less than eight stitches to an inch; they must be stitched within four-tenths of an inch of each edge, and the two edges of the seam felled down upon the same side, to prevent the powder from sifting through. The edges of the bottom are felled down upon the sides.

The bags, when filled, must be tied with woollen thrums.

185. Cartridge-Bags for Saluting Charges.—Old cartridge-bags which have been condemned for service charges are to be repaired and used for saluting charges; and whenever it is necessary to make bags expressly for the purpose, or for immediate use, they may be formed by sewing together two rectangular pieces with semicircular ends.

186. Inspection.—The material especially procured for cartridge-bags is to be carefully inspected to detect any mixture of cotton with the wool, by burning a few bits taken at hazard from each piece; or, by dissolving it in a solution of 1 ounce of caustic potassa in a pint of water—the cloth to be put in when the water is boiling, which is to continue until dissolution takes place. The texture of the stuff is also to be examined and its strength tried, such standard for the latter being established as may be found sufficient to insure perfect efficiency.

After being made up, the empty bags are to be inspected, and those which are sewed with too long stitches, or in any other than the prescribed manner, must be rejected. The dimensions of each bag are to be verified, first by laying it flattened out, between two marks on a table showing the width of a pattern bag. A variation of 0.1 inch greater or less is allowed. The bags are also to be tried on mandrels, or formers, made according to the dimensions given on the preceding page.

187. Preservation From Moths.—Serge or any other woollen material employed for making cartridge-bags is never to be exposed on the shelves in store, either in the piece or when made up. It is to be protected by packing with the hydraulic press, by sewing it up in linen cloth, or by enveloping it in water-proof paper, hermetically sealed.

An infusion of coloquintida, in the proportion of 15 1/2 grains Troy to a quart of water, is said to be a good preservative against moths. In case of using this preparation, the cartridge-bags should be steeped in the infusion, and, after being thoroughly dried, may be packed by the hydraulic press, and headed up in old whiskey barrels, if stored on shore, or packed in empty tanks, if on board ship.

Cartridge-bags, as well as the material for making them, must be frequently examined, to prevent their being damaged by moisture, as well as to guard against moths.

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FOOTNOTES:

[1] Primers and percussion-caps should be divided into two or three lots, and stowed in different parts of the ship, so that an accidental explosion would not deprive the ship of the means of firing cannon and small arms.

[2] The dimensions of those for the XV, IX, X, and XI inch guns, which have Corner chambers, and cannot be conveniently tabulated, will be furnished to all vessels mounting such guns. The formers for inspection of bags will have the forms and dimensions of the Gomer chambers less 0.87 inch for the IX-inch, 1.0 inch for the X-inch, 1.15 inch for the XI-inch, and 1.50 inch for XV-inch guns, for windage at the large end, in accordance with the flat patterns furnished for cutting.

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CHAPTER II.

MAGAZINES AND SHELL-ROOMS.

CONSTRUCTION, LIGHTING, STOWING, AND FLOODING.

188. No details of internal arrangement should be more carefully considered and executed than those relating to the stowage and delivery of powder, since a defect in these particulars, apparently insignificant, may lead to the instantaneous destruction of the ship; or, with the incendiary and explosive projectiles now used, to her becoming, comparatively, an easy prey to an antagonist. Every possible precaution, therefore, is to be taken to accommodate the full allowance of powder completely; to guard it to the utmost against injury and accidental explosion; and to deliver it at the magazine, as required, with facility and certainty. To these ends, and in view of the fact that all the powder for great guns is now put up in cubical copper tanks, made water-tight, THE FORM OF MAGAZINES should be as nearly rectangular as the shape of the vessel will admit, and they should be built strong enough to resist sufficiently the effect of her working in heavy weather, and also the pressure of water they will have to sustain in case of being flooded.

189. All magazines should have a light-box for each alley at one end, and a passage to deliver powder at the other; and the magazine and its passage, considered as one, must be made perfectly water-tight by caulking the bottom and sides, and then lining them internally, first with white pine boards, tongued and grooved, and again with sheets of lead of extra thickness, soldered together, over these boards. Both these linings are to extend entirely over the bottom or floor, and all the way up to the crown on all the sides.

190. When the magazine reaches the ceiling of the ship it must be battened off two inches; the lining of the floor must be battened up one, and also the magazine-deck, so that water leaking through the sides of the vessel may run by and under, and not into the magazine.

An external lining of sheet-iron must also be resorted to as a protection against fire, and to prevent the intrusion of rats.

191. A magazine aft in a ship is to have its passage for delivering powder adjoining its forward part; and one forward in a ship is to have this passage adjoining its after part, in order that it may not be necessary to pass the powder over the light-box scuttle.

192. As many doors are to be cut in the bulkhead separating this passage from the magazine-room as there are alleys to be left in the latter, between the racks or shelves on which the tanks are stowed, and these doors must correspond with those alleys. They are not only to afford a means of entrance to the magazine, but also for passing the tanks in and out. Through the upper part of each door a small scuttle is to be cut,—two, if necessary,—for the purpose of passing the cartridges out of the magazine-room with the door itself closed; and it is to have a lid so arranged as to open outwards only, and to close of itself when the scuttle is not actually in use.

193. Sailing ships-of-the-line and frigates should have two alleys for each magazine. In screw-vessels of large class, where the shaft will interfere with this arrangement, two alleys for the forward magazine. In smaller vessels one alley will suffice. In all cases the alley is to be not less than two feet and ten inches in breadth, and it ought to be more, if practicable, to prevent confusion and delay. Each alley is to be illuminated by a separate light.

If there is room in the magazine, there should be space left, at the end nearest the light, for a man to pass from one alley to the other without going into the passage.

194. Ships with two magazines—one forward and the other aft—are to have them as nearly equal, in point of capacity, as the shape of the vessel and other circumstances will admit.

Magazines should be constructed as low down as possible. Their floors may rest on the keelson, but should not come below it. Their height should be equal, only, to an exact number of times the height of a powder-tank when lying on its side, in addition to the thickness of the shelving. An additional inch for each shelf should be allowed for play or spring. The whole height in the clear should be limited by the condition that a man standing on the floor may reach the upper tier of tanks with ease. Four tiers of 200-lb. tanks, three of them resting on shelves two inches thick, and the other on inch battens on the magazine-floor, will, with an allowance of one and a half inch for play and spring, require a height, in the clear, of six feet two inches. Both safety and convenience would suggest this as the maximum limit in height, even for the largest magazine. Three tiers of these tanks will require a height, in the clear, of about four feet eight inches.

If, however, in ships of great draught of water, it should be found practicable to extend the height of a magazine so as to accommodate five tiers of tanks, then the lower or ground tier may be laid so as to occupy the whole of the magazine-floor; and on the top of this tier, in the alley-way, a light false bottom is to be placed for the men to stand upon to enable them to reach the upper tier, which is the one that should first be exhausted. This false bottom should be made of gratings, and in sections convenient for speedy removal.

195. When it is impossible to avoid extending the sides of the magazine so far out towards the skin of the ship as to leave only an air-passage on either side, the crown should be at least six feet below the deep load-line.

In all cases where this crown is less than six feet below that line, the sides should be made susceptible of protection by allowing a space to interpose materials, such as sand, coal, or water in tanks, between them and the inner planking of the ship.

An average space of six feet or more on both sides will be sufficient. Under no circumstances, however well the sides be guarded, should the crown of the magazine, if it can be avoided, be less than four feet below the deep load-line.

196. It is proper to add, in connection with this most important subject, that in order to increase security against the effects of lightning, a magazine should be placed, if practicable, so as not to include a part of a mast.

197. All the metallic fixtures about a magazine, delivering-passages, and light-rooms, must be of copper.

198. Each delivering-passage is to have, for the distribution of powder, at least as many passing-scuttles communicating with the orlop or berth deck as there are chains of scuttles above. The powder-man will thus always find at the scuttle the proper passing-box.

MAGAZINE-COCKS.

199. Each magazine, as a whole—that is, including the delivering-passage—being made, as stated above, water-tight, is to be provided with an independent cock for filling it rapidly with water; a waste-pipe leading from above the upper tier of tanks to carry off the superfluous water; and a cock just at the floor for letting the water off when the magazine is to be emptied after having been flooded. Both the cocks must be turned from the deck above, each having a lever to its spindle for the purpose, distinctly marked, with engraved letters, what it is and how it is to be used, and kept secured by a proper lock, the key of which is to be kept among those of the magazines. A short pipe to lead the water down into the hold is to be attached to the emptying cock, and with this the waste-pipe is to connect. All are to be well boxed over for protection against injury. A perforated disk, or strainer, is to be secured inside of the hole, at the upper part of the magazine, for the waste-pipe. All couplings of hose shall conform to the general naval standard.

LIGHTING THE MAGAZINE.

200. The magazine is to be lighted by means of one regulation-lamp, to correspond with each alley of the magazine-room, placed in a box arranged for the purpose. This box, of which a portion of the magazine bulkhead forms a part, is to be lined, internally, with soldered sheets of copper, and have a few inches of water in it whenever the lamp is lighted. The entrance to it is at the top, through a scuttle in the deck large enough to admit the lamp. For single-decked vessels this scuttle may be surrounded by a composition coaming pierced with holes one-fourth of an inch in diameter, on the forward and after sides near the top. The cover must be so arranged that, when placed in one position, all the holes will be closed—by turning it half round, they are all open; thus supplying air to the lamp and carrying off smoke. In the portion of the magazine bulkhead just alluded to, and so as to throw as much light as possible into the magazine-room, an opening with great bevelling is to be cut, which is to be covered by two plane glasses of suitable thickness, somewhat separated from each other, one of which, that next to the lamp, must be permanently fixed; and the other, or that next to the magazine, is to be let into a wooden frame so that it may be easily removed, and thus both glasses cleaned at any time with convenience and safety. The glasses are to be held in place by brass screws, after being closely fitted and having their edges made perfectly tight. A small dome or reversed funnel of copper, where it can be conveniently done, is to be placed above the lamp and fitted with a pipe of the same metal to convey the smoke off. This pipe may pass up through the covering of the light-box, which is to have a plug-hole, lined with brass, for the purpose, and then led farther, if necessary, taking care, however, to consult perfect safety throughout.

The admission of air to the light-box may be from the division of the hold in which it is placed, by small holes, near its top, through its side or back, protected with copper wire-gauze, inside and outside of the box.

The ceiling and bulkheads of all magazines and shell-rooms should be thoroughly whitewashed.

STOWING THE MAGAZINES.

201. In the stowage of magazines, reference must be had to the Gunner's duties (Art. 36, Part I.), and to Arrangements for Delivering and Distributing Powder (Art. 180, Part I.). Ledges on the shelves, or a bar of wood to ship and unship with facility, will be provided for each tier of tanks, on both sides of the alleys, to secure them from getting out of place when the ship rolls.

The Inspector of Ordnance will furnish the commander of the ship with an exact plan of the magazine and shell-rooms, which shall be returned to the Inspector of the Yard at which the ship refits or is placed in ordinary, with any suggestions the Commander may have to make relative to practicable changes which will render the service more safe or convenient.

SHELL-ROOMS.

202. Rooms for the stowage of loaded shells require the same care in construction and protection against an enemy's shot, and in provision for lighting and flooding, as magazines. Therefore, they should always be built with reference to these objects, as well as to affording room enough to accommodate conveniently the number of loaded shells allowed in their boxes, stowed in bulk. Each should have one light, arranged like those for magazines.

203. In vessels partially armed with shell-guns, the best place, perhaps, for these rooms is immediately forward of the spirit-room, but not communicating with it; and in those armed entirely with such guns, the additional shell-rooms necessary may be, perhaps, more conveniently placed abaft, and adjoining the delivering-passage of the forward magazine, than elsewhere.

204. With the introduction of rifled cannon, and various special projectiles, it is essential to devote more care to the stowage of shells, in order to avoid confusion in battle. Not only each kind and calibre, but each length of fuze, is to be stowed in separate tiers.

DAMPNESS OF MAGAZINES AND SHELL-ROOMS.

205. Sponge clipped in a solution of salt water, dried and weighed, is a means of ascertaining if dampness exists in these places. If it become heavier, the room is damp.

VENTILATION.

206. Provision must be made, by means of grating-hatches, for sufficient ventilation in action, to supply the magazine-men with fresh air, and allow the dampness caused by perspiration to pass off; and fan-blowers are to be fitted to increase the supply of fresh air, and assist the ventilation. The magazine should be opened and aired, at least once a fortnight, for a few hours, on bright, clear days.

C.K. Stellwagen, del. Lith. by J.F. Gedney, Washn.

C.K. Stellwagen, del. Lith. by J.F. Gedney, Washn.

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CHAPTER III.

GUN-CARRIAGES, GEAR, IMPLEMENTS AND EQUIPMENTS.

GUN-CARRIAGES.

207. All gun-carriages shall be constructed in exact conformity to the drawings furnished by the Bureau, and no alterations whatever will be permitted without its express sanction.

The Inspector of Ordnance will keep approved copies of all plans, and, in order to insure uniformity, will report to the Bureau any deviations from the standard drawings which he may observe in carriages received from other Yards.

The spaces required for efficient working of all guns are represented in diagrams X, Y, Z, and these, as well as the distances between pivot-centres, sizes and positions of bolts, are to be strictly adhered to.

The distance between pivot-centres of all XI-in., X-in., IX-in., and 100-pdr. carriages shall be either 142 or 117 3/4 inches, depending on the breadth of beam, position of hatches and other obstructions, and shall not be deviated from except by explicit directions of the Bureau, on a report of the particular circumstances in each case.

For the 60-pdr. Parrott, 130 inches between centres; and for the 30-pdr., 120 inches.

The sizes of sockets and pivot-bolts are established as follows:

	For XI-in., X-in., IX.-in., and 100-Pdr.	For 60, 30, and 20-Pdr.
	Inches.	Inches.
Length of bolt under the head	18.	14.
Diameter of bolt	4.	3.
Diameter of hole in socket	4.1	3.1
Diameter of hole in boss	10.5	8.
Height of boss	1.5	1.1

Slot in the pivot-plate, 1/16 larger than the boss.

For XI-in., X-in., IX-in., and 100-pdr. carriages, the fighting and shifting sockets are bossed, the housing-socket plain.

For 60-pdr., 30-pdr., and 20-pdr. carriages, the shifting-socket alone is bossed.

For broadside-guns, the following positions for bolts are established:

	20 and 24 in. Port-sills.	16 and 18 in. Port-sills.
	Inches.	Inches.
Height of centre of lower bolt from deck	14.75	10.75
Distance between the bolts	3.75	3.75
Distance of centre of 1st bolt from side of port	14.	14.
Distance of centre of 2d bolt from side of port	22.	22.
Distance of centre of training-bolt from side of port	36.	36.
Height of training-bolt from deck	21.	14. & 16.
Height of securing-bolt (side-tackle bolt) above port-sill	8.	8.

For IX-in. guns, the port-sill should not be less than 20 inches in height, and no port-sill less than 16 inches; otherwise, the carriages will not give sufficient elevation, and the position of the Gun Captain in aiming is exceedingly awkward and inconvenient.

Scraping and staining gun-carriages or keeping them bright is prohibited; they should be kept well painted, and the trucks, axletrees, and trunnion-holes oiled.

All new work shall be primed with red-lead.

Wrought-iron Broadside carriages, for IX-inch, new 8-in. of 6,500 lbs., and 32-pdr. of 4,500 lbs. shell-guns, have been designed by the Ordnance Bureau, submitted to trial with success, and are being issued for service at sea.

GUN-GEAR.

208. Breechings for all guns are to be made of the best hemp, of three-stranded rope, shroud-laid, and soft; and for smooth-bore guns not to measure less than seven and a half nor more than eight inches in the coil, excepting those for IX-inch guns, which are to measure nine and a half inches, and for XI-inch ten and a half inches.

209. The breeching-bolts must never be of less dimensions than those prescribed by regulation, and there must be double sets for the IX and XI inch guns.

210. In fitting breechings, a thimble is to be spliced into one end, the strands stuck through twice, and marled down. A thimble is to be turned into the other end, so that the length of the breeching may be conveniently altered. Thus fitted, when the gun is run in and levelled, breechings must be long enough to allow the muzzle of the gun to come a foot inside of the upper port-sill, if the breadth of the vessel will allow it. With guns of violent recoil this distance may be advantageously doubled, where there is room enough, as thereby the strain will be much lessened.

Breechings are neither to be covered, blackened, nor rendered less pliable in any way.

Lith. by J.F. Gedney, Washn. C.K. Stellwagen, del.

BREECHINGS.

Class of Gun.		Length of Breeching when Cut.	Length of Breeching when Finished.	Circumference of Breeching.	Thimble.				Weight, including Thimble.
					Diameter.	Depth.	Radius of Score.	Diam. bolt-hole.
		Feet.	Feet.	Inch.	Inch.	Inch.	Inch.	Inch.	Lbs.
Pivot.
XI-inch		38.	32.	10.5	6.	4.	1.75	2.05	172.
X-inch		37.5	31.5	10.	6.	6.	1.75	2.05	170.
IX-inch		34.	28.5	9.5	6.	3.6	1.6	2.05	110.
100-pounder		37.5	31.5	9.5	6.	3.6	1.6	2.05	130.
60-pounder		33.	28.	8.	5.5	—	1.3	1.55	91.
30-pounder		27.5	23.5	7.	5.	—	1.2	1.55	43.
20-pounder		26.	21.	6.	4.	—	1.0	1.55	40.
Broadside.
XI-inch		38.0	32.0	10.5	6.	4.	1.75	2.05	172.
X-inch		34.5	28.5	10.	6.	4.	1.75	2.05	160.
IX-inch		31.5	25.5	9.5	6.	3.6	1.6	2.05	100.
8-in.	63 cwt.	28.	23.3	8.	5.5	—	1.3	1.55	76.
8-in.	55 cwt. 6,500 lbs.	27.	22.3	8.	5.5	—	1.3	1.55	72.
32-pounder	57 cwt.	28.5	24.	8.	5.5	—	1.3	1.55	76.
32-pounder	42 cwt. 4,500 lbs.	26.	21.5	8.	5.5	—	1.3	1.55	70.
32-pounder	33 cwt.	23.5	19.	8.	5.5	—	1.3	1.55	65.
32-pounder	27 cwt.	22.	17.5	8.	5.5	—	1.3	1.55	61.
Broadside Rifle.
100-pounder		35.5	31.	9.5	6.	3.6	1.6	2.05	115.
60-pounder		28.	23.5	8.	5.5	—	1.3	1.55	80.
30-pounder		25.5	21.5	7.	5.	—	1.2	1.55	39.
20-pounder		23.	17.5	6.	4.	—	1.	1.55	34.

211. Gun-tackle falls will be made of Manilla or such other pliable rope as may be directed from time to time by the Bureau of Ordnance. It is prohibited to blacken them or to diminish their pliability. Three-inch rope will be found large enough for the heaviest, and from 2 1/2 to 2 1/4 inch for the lighter guns.

The rope being well stretched, the falls are to be cut of sufficient length to allow the full recoil, leaving end enough to hitch round the straps of their inner blocks, when hooked to the middle bolts.

212. Blocks for gun-tackles should have pins of hardened copper, turned smooth, and sheaves of lignum-vitæ without bouching. Those to reeve 3-inch falls to be 10 inches, those for 2 1/2 inch falls 9 inches, and those for 2 1/4 inch falls 8 inches long. The hooks of gun-tackle blocks are not to be less than one and a half inch diameter at the bend for heavy, and one and a quarter for light, broadside-guns.

Metallic blocks with nibs, which keep the blocks fair with the falls, and thus prevent the falls from fouling in the recoil, are to be supplied to all Marsilly and heavy pivot carriages.

GRIOLET.

213. The Griolet-Purchase for dismounting guns on covered decks is composed of—

A toggle-block, made of elm or oak, the outer end or head of which is made rather larger in diameter than the inner one, which exactly fits the bore of the gun. The head has two sheaves in it, so as to form the lower block of the muzzle-purchase, and is bound at the outer end with an iron band.

A double cascabel-block of iron is made either with a shackle or to fit between the jaws of the cascabel, where it is secured by the cascabel-pin. The iron pins on which the sheaves revolve are formed with eyes, for the convenience of hitching the standing part of the purchase.

Two iron treble-blocks, one for the muzzle and the other for the breech-purchase.

The muzzle-purchase block is so fitted as to be either shackled or toggled to the housing-bolt above the port, and the breech-purchase block has an iron strap terminating above, with an eye by which it is shackled to a bolt passing through the deck above the gun. This bolt has an eye in one end, and a screw or key-slit at the other, and, when in place, is secured above the deck with a nut or key, between which and the deck a washer of hard wood or iron of suitable breadth and thickness is placed.

The hole through which this bolt is put should be directly above the cascabel-block when the muzzle of the gun is under the housing-bolt, and may be bored at the time the gun is to be dismounted; it is to be stopped afterwards with a plug of wood coated with white-lead.

But as it is desirable that every division on the gun-deck should be exercised in mounting and dismounting its guns, a hole may be made in the deck above each division and bouched with a composition screw-tap.

The purchase-falls should not be less than three and a half inches in size, and should be made of Manilla rope, of sufficient length to reeve full, the gun being supposed to be on deck and the upper blocks in place, allowing also sufficient end for splicing in the thimbles and hitching the standing part of the purchase when rove.

An iron thimble, large enough to hook the double-block of a side or train tackle, is spliced into the end of each purchase-fall.

SELVAGEE WADS.

214. Selvagee wads are made by the wad-machine at the Navy Yards. This consists of pairs of disks adapted to each calibre of guns, which being placed face to face on a spindle and keyed, present an annular score, grooved in such a way as to make, when filled, a grommet of the requisite size. Transverse notches are cut in the circumference of the disks to the bottom of the score, for the convenience of marling the wad before taking it off the mould.

Lith. by J.F. Gedney, Washn. C.K. Stellwagen, del.

In making the wad, the end of a rope-yarn is fixed in the score, and the mould is turned by a crank until the score is filled. The grommet thus formed is marled like a selvagee strap, and a section of about an inch is taken out of it, in order to make the wad, when swelled by dampness, enter the bore of the gun readily.

Selvagee wads should be made neither too hard nor too soft; and to avoid either of these extremes, a sufficient number of hitches only will be taken to give the wad the consistency required for service.

Sections of one-third or one-fourth of these wads will answer as well, in case of need.

MAGAZINE-SCREENS.

215. Are made of thick fearnaught, or of double baize, with holes through which to pass the powder; these holes to be covered by broad flaps of the same material. One screen is to be hung abaft, and another forward of the magazine passing-hatch and scuttles in sloops-of-war; in ships-of-the-line and frigates, one is usually to be hung abaft the fore, and one forward of the after, magazine-scuttle; but as ships are differently arranged, two to each magazine will be allowed, if required.

Canvas chutes for returning empty passing-boxes are to be supplied to each scuttle.

MAGAZINE-DRESSES.

216. Are to be of worsted, like a simple shirt, to reach to the knees—no metal buttons to be worn.

The shoes must be made wholly of cotton canvas or buckskin. In hot climates or warm weather generally, the naked feet are preferred. India-rubber and woollen slippers are prohibited.

RATTLES FOR CALLING BOARDERS.

217. To be made like those used by watchmen, of white oak, or some other similar wood. Rattle, 12 inches long; ratchet, 2 inches in diameter; spring, one inch in width, and of sufficient thickness and elasticity to produce the requisite sound. Weight enough should be given to the butt to cause it to revolve round the handle with ease.

Fixed rattles of greater power will be attached to suitable places on each deck.

SHELL-WHIPS.

218. To be made of two-inch rope, rove through two single blocks one above the other, in the shell-hatchway, and the ends knotted together. A hook is fixed on each part of the whip, near the block, so that the parts being bowsed on alternately, a full box is brought up on one hook and an empty one lowered by the other, at the same time.

FLASH-PANS.

219. Shallow copper bowls, large enough to hold an ounce of powder, with a handle two feet long, to be supplied to all vessels.

DARK LANTERNS.

220. To be made of copper, tinned inside, with two handles at the side, that the shade may be turned without taking hold of the top. The whole height, 12 inches; diameter, 4 inches.

BOAT GRAPNELS.

221. Are made of round iron, quite light, for throwing into the rigging or chains of the enemy, for the purpose of holding on when boarding; their prongs are barbed.

Six feet of small chain are to be attached to the ring, and connected with six fathoms of one and three quarter rope.

TARGETS.

222. In the construction of targets for practice at sea, the chief object will be to give buoyancy and stability to the screen, with sufficient development of its surface. To these ends, whiskey or beef barrels, supporting boards of sufficient length, will afford staging for the masts, yards, and screen; the heel of the mast passing through the stage, and having ballast attached to it. The stage should be so fitted as to be readily put together when wanted, and taken apart for stowage.

Harbor targets may be anchored, or supported on stakes; but it would conduce to good practice to stretch a screen of sufficient length to show, distinctly, four or six ports, with the proper intervals between. This will the better exhibit the lateral effect of the firing of each gun, and of the concentration of fire from several guns at known distances.

PACKING-BOXES.

223. Cartridges for small arms, primers, spur-tubes, percussion-caps, spare fuzes, false-fires, blue-lights, port-fires, and signal-rockets, will generally be supplied to vessels in boxes, in which they can be kept with little liability to injury, until wanted for use. (See [Part I., Page 10, Art. 42.])

These boxes are to be safely kept and returned into store, or accounted for in the same manner as other articles of Ordnance stores, by those persons in whose charge they may be placed. They will be held pecuniarily responsible for their loss.

GUN-SLINGS

224. Must be made of chain of 3/4-inch iron, and tested, to secure proper strength; the rings are to be of 1 1/4-inch iron. The length of the slings should exceed by one foot that of the longest gun on board. The two parts should be parcelled and marled together for a space of two feet before and one foot behind the trunnions of the longest gun, and a piece of three-inch rope spliced around both parts in the wake of the parcelling, long enough to take four or five turns round the chase of the largest gun.

TRUNNION-SIGHT FOR MORTARS AND PIVOT-GUNS.

225. The trunnion-sight is designed to be used only when the required elevation passes the limits of the other sights. It is formed of a bar of mahogany, or other hard wood not liable to warp, of about forty inches in length, two inches wide, and one inch thick, with a brass notch at the rear end and a point at the other, fixed in, and parallel to, the upper edge. It is attached, by a stout thumb-screw, to the axis of the left trunnion, around which it revolves when the screw is slack.

A semicircular plate, graduated to degrees, is attached to the bar, so that the sight may be used with the tables showing the corresponding ranges of the several classes of guns with their distant firing-charge. (See [Tables of Ranges, Appendix D.])

The upper edge of the sight-bar corresponds with 0° when the line of sight is parallel to the axis of the bore. A small level let into the upper surface of the rear end of the bar shows when the bar is level.

In using this sight, the thumb-screw is first loosened, and the rear end of the sight raised until the mark on the trunnion coincides with the degree of elevation required for the range, as given in the Tables: clamp the thumb-screw, and elevate the gun until the bubble is at 0°, then give the lateral training.

226. Tangent-sights placed on the side of the breech, with a fixed front sight on the rimbase, as in rifled cannon, will hereafter be supplied to all pivot-guns; and these will give the sight with equal accuracy at all elevations.

RAMMERS AND SPONGES.

227. Rammer-heads are to be made of well-seasoned ash, birch, beech, or other tough wood, of the form and dimensions given in the drawings furnished by the Bureau to the different Navy Yards. The face of the rammer is hollowed, so as to embrace the front of the ball and press the selvagee wad home in its place. A hole is bored lengthwise through the head to admit the tenon, which is fastened by a pin of hard wood, three-tenths of an inch in diameter, passing transversely through the head and tenon. The diameter of the staff is 1.75, and that of the tenon 1.5 inch. The diameter of the rammer-head will be 0.25 inch less than that of the bore or chamber to which it is adapted.

For all chambered guns except those of the Dahlgren pattern, the rammers will be adapted to the chamber, but, as above described, will answer equally well for the shot and selvagee wad.

Staves are made of tough ash, and are one foot longer than the bores of the guns for which they are intended: they are to have grooves 1/16 of an inch deep and 1/4 of an inch broad cut in them to show when the "ordinary charges" are in place, and, by due allowances, the others also.

For rifled cannon, rammer-heads are made of composition, of the pattern prescribed by the Bureau.

228. Sponge-heads are to be made of poplar, or other suitable light wood. A hole 1.5 inch in diameter is bored through the axis to admit the tenon of the staff, into which the worm is previously secured by means of a brass pin which passes through an eye in its shank and the tenon. The worm is intended to project half an inch beyond the face of the sponge-head, when the tenon is in place, and to have free play back into its socket when pressed against the bottom of the bore. It must be two inches in length and one and a quarter inch in diameter, made of elastic brass or composition wire two-tenths of an inch in diameter, and tapering at the points, so as to preserve its elasticity and firmness. It is to be left-handed, in order to act when turned to the right, or with the sun.

The wood of which sponge-heads are made should be well seasoned, and gotten out of a size but little greater than the diameter of the heads for which it is intended, so that there may be as little shrinkage as possible in the finished heads.

The heads, when finished, should also be primed with several coats of boiled linseed oil or varnish, as the porous wood of which they are made is apt to become water-soaked, or to split on exposure to the air.

229. For chambered guns the sponges must fit the chambers and slopes, and a portion of the main bore, as shown in the drawings furnished by the Bureau. When made of wool, the whole surface is covered, and so sheared as to have no windage, and to be even with the points of the worm, that they make take effect. The heads for woollen sponges should be one inch less in diameter than the bores or chambers of the guns for which they are intended.

In future, sheepskins will not be allowed, but covers for sponge-heads made up ready to slip over the head and be tacked on.

230. The heads for the sponges of unchambered guns are to be eight inches long; and all sponge-heads intended to be covered with woollen material must be slightly tapered and secured by a thin copper hoop, fastened with copper tacks, on the inner end.

231. For Bristle Sponges the heads must be 1.5 inch less in diameter than the bores or chambers for which they are designed. The bristles are to be sheared so as to work easily and leave no windage. The worm must project one-fourth of an inch, in order to take the bottom of the bore, and special care is to be taken by the Inspector that it has both the necessary stiffness to act efficiently and elastically enough, when pressed home, to yield sufficiently to allow the bristles to act also. Spiral spaces extending the whole length of the sponge-head, including the portion adapted to the main bore in chambered guns, are to be left, in order to bring out the unconsumed portions of cartridges. These spaces must be left-handed like the worm.

Great care is necessary, in stowing them, to prevent the bristles from being crushed down by contact with hard substances. For this purpose fenders will be provided with copper tacks, on the inner end.

One will be allowed to each division, for each calibre, for cleaning guns.

232. Sponge-staves are to be made of tough ash, 1.75 inch in diameter, and must be 18 inches longer than the bores of the guns for which they are intended.

233. Sponge-caps are made of duck, and, except for spar-deck guns where they are exposed to the weather, should not be painted, but they, as well as the staves, should be kept clean by scrubbing. A becket should be attached to the end to haul them off by.

Sponges should be washed carefully and dried after use before putting the caps on, and frequently examined and dried to prevent their rotting.

ROBINSON'S WORM.

234. This worm consists of a screw, 1 1/4 inch in diameter, of two turns, at the end of a cylindrical iron shank, with a socket and straps riveted to the staff, which is 1.5 inch in diameter. The worm is supported in the axis of the bore by means of a guide-ring of composition, kept in place on the shank, six inches from the end, by a shoulder and forelock.

Thus adjusted, it is used to draw the junk-wad and cartridge; the latter being laid hold of by the tie, if the staff be held in the axis of the bore, is uninjured.

When the ring is removed the worm will be equally efficient in drawing the selvagee wad.

LADLES.

235. Ladles, when required, are to be made according to the patterns sent to each of the Navy Yards. Ladles which may be on hand are to be tried in drawing projectiles from the guns before they are issued for service. The Ladle will not draw rifle projectiles, and should not be used for that purpose.

SCRAPERS FOR BOTTOM OF BORE.

236. These consist of two steel blades, crossing each other in the middle, and having their edges conformed to the curve of the bottom of the bore. They are inserted in a sponge-bead, and are designed to remove the cake usually caused by the adherence of the bottoms of the cylinders to the bottom of the bore.

The edges of the scrapers are so bevelled as to act only when turned to the right, or with the sun.

Scrapers are also to be supplied for rifled cannon, made to clean a groove and the adjacent lands.

ORDINARY HANDSPIKES.

237. Handspikes are to be made of well-seasoned white hickory, of the form and dimensions directed by the Bureau. They are always to be shod, stained black, and oiled. The Ordnance Officer of the Navy Yard will ascertain that they ship freely in the training-loops or sockets, and that the toe is sufficiently rounded not to cut the decks when held vertically.

Details of Handspikes.			No. 1.	No. 2.	No. 3.
Length	Total	in.	64.	60.
	Square part	in.	20.	20.
	Octagon part	in.	6.	6.
	Round part	in.	38.	34.
	Shoe	in.	18.	18.
Diameter	of square	in.	2.75	2.50
	of small end	in.	1.75	1.6
Radius of quarter round		in.	4.5	3.5
Weight		lbs.	16.	12.

ROLLER HANDSPIKES.

238. There are two sizes of roller handspikes: No. 1 for the IX-in. shell-gun and 100-pdr. Marsilly, or two-truck carriage; No. 2 for all other guns.

They are composed of—the head and socket of bronze, handle of hickory, and the roller of lignum-vitæ.

The boss on the head makes, with the handle, an angle of 70°, and, when vertical, lifts the carriage half an inch (0.5).

Commander Beaumont's roller handspike has been adopted.

It is a common error of seamen to stoop, with a view of raising the carriage higher. The lift is greatest when the end of the handle is at the hip.

Details of Roller Handspikes.			No. 1.	No. 2.
Length	Extreme	in.	70.5	66.
	of handle	in.	63.	62.5
	of socket	in.	12.	7.5
	of boss	in.	1.6	1.3
	of boss from centre of roller	in.	4.5	3.6
	of axle-pin	in.	9.5	7.5
Diameter	of roller	in.	4.5	2.5
	of socket	in.	2.9	2.5
	of hole in socket	in.	2.6	2.25
	Small end of handle	in.	1.5	1.50
	of hole for axle-pin	in.	.75	.62
Width	of roller	in.	4.5	2.5
	Exterior of head	in.	9.00	7.00
Weight		lbs.	32.	19.5

IMPRESSION-TAKERS.

239. All vessels carrying XI and IX inch guns, and all iron rifles, are to be furnished with an impression-taker and wax. Impressions of the vent and bore, as described in Art. 57, are to be taken after every ten shotted rounds in practice, and at the close of an action. The last one should be preserved for comparison with the succeeding one; and when, in the opinion of the Commanding Officer, the wear becomes excessive, or a decided crack shows itself, a duplicate must be forwarded to the Bureau for examination. In forwarding them, they should be tacked on a piece of thin board secured in the bottom of a box. If wrapped in cotton or oakum they are generally defaced. The date, number of fires, Register Nos. of guns, ship from which forwarded, and other remarks written and pasted on the under side of the box-cover.

In expert hands any small spar—such as a boat's mast—will take the impression equally well.

PASSING-BOXES.

240. Passing-boxes are to be made of strong and well-tanned harness or sole leather, strongly sewed, or of such other material as may be directed.

For 8-inch and 32-pounder guns they are to be of sufficient height to contain two near-firing charges.

Their diameters, in the clear, must be half an inch greater than those of the cartridges they are to contain.

Their tops must be distinctly lettered, in letters one inch and a half long, with the calibre and class of gun they are intended to serve, and made to slide on the beckets.

241. All passing-boxes are to be painted black, with the calibre and charge painted in white letters two and one-half (2 1/2) inches long on the side, and one and one-half (1 1/2) on the top.

242. If, however, there are any guns of the same calibre on spar-decks requiring lighter charges, the lower half of the box shall be painted white.

For gun-decks in similar cases the lower half shall be painted red.

FIRE-TUBS.

243. Fire-tubs should be made of oak, of the patterns furnished by the Bureau, the hoops being of iron. The top is to be provided with a stout hoop of wood, to ship and unship, with a grating across it of stout copper wire, the meshes of which must be small enough to prevent the passing-boxes from falling into the water when struck over the tub.

FIRE-BUCKETS.

244. Fire-buckets should be made of light well-tanned sole leather, according to pattern.

A few Rubber buckets have been issued for trial and report.

THE GROMMET MUZZLE-LASHING FOR HOUSING GUNS.

245. Consists of a grommet made of rope double the size of the gun-tackle falls, with two cringles worked into it for the frapping lashing, which will be of stuff half the size of the tackle-falls.

The grommet will be made large enough just to slip over the swell of the muzzle when the bight is over the housing hook-bolt, and the gun is in position for housing. It will be wormed throughout, and parcelled in the wake of the housing-bolt and frapping lashing, and where there is no swell, in the wake of the muzzle-ring.

Where the housing-bolt is an eye-bolt, the grommet is secured to it by means of a toggle which has a lanyard.

FUZE-WRENCHES.

246. For the Navy time-fuze these are made of steel, with a round shank, four inches long, four-tenths of an inch diameter. Prongs round, one and a half inch long, three-tenths of an inch diameter. Cross-handle of wood, with small forked screw-driver in one end for water-cap. The prongs of the wrench are flattened at the ends, and are nine-tenths of an inch apart.

A three-armed wrench is also required for the Parrott, Schenkl, and Hotchkiss fuzes, all of which differ.

Two to be allowed to each shell-room.

RIGGING STOPPERS.

247. Standing rigging, when stranded or shot away, is most readily and effectually secured for the moment by using stoppers composed of two small dead-eyes, fitted with double selvagee tails and lanyards, of sizes suitable to the rigging, whether lower or topmast. These are to be fitted on board ship, and set up by means of pendant-tackles or jiggers, as the case may require.

HARNESS-CASKS FOR BOATS.

248. For expeditions, the launches and first cutters of all vessels are each to be provided with a week's supply of pork, sufficient for all the boats' crews of the ship, kept in quarter barrels or kegs, adapted to the form of the boat and to convenient stowage.

ACCOUTREMENTS FOR CAPTAINS OF GUNS, BOARDERS, AND SMALL-ARMS MEN.

249. Waist-Belts, to be made of buff leather—grained leather becomes stiff and horny when exposed to the sea-air—two inches wide, and from forty to forty-four inches long; a pattern buckle has been adopted.

The same belt is used by Captains of guns and boarders, as well as by small-arms men and the crews of field-howitzers; the frogs and boxes to hold the arms and ammunition being fitted with loops to slip on and off the belt as circumstances require, and in the following order:

1st and 2d Captains of guns, and of field and boat howitzers, wear the primer-box in front; if they are boarders, the sword on the left and the pistol-frog on the right hip. These equipments, consequently, will be slid on towards the loop end of the belt, in the order just named.

Other boarders, and guns' crews of howitzers when used as field-guns, wear their arms, as in the preceding case, without the primer-box.

Men armed with muskets, and acting on shore, will wear musket cartridge-boxes, fitted with frog and scabbard for bayonet on the waist-belt.

Men who may be armed with carbines on shore duty will wear cartridge-boxes with waist-belts. For boat duty, or when armed with pistols and swords, they will wear the waist-belt with the proper frog and boxes.

250. Instead of the sword-frog, the sword scabbards of Admiral D.D. Porter's pattern are fitted with a loop to slide on the waist-belt. This scabbard also dispenses with the brass mountings, which are replaced by leather ones. The whole is fastened by copper rivets, instead of being sewed.

251. Primer-Boxes, of black bridle leather, rectangular in form, and of the size to contain, loosely, the tin packing-box. Flap covering the top and front with a button-hole strap one inch in width, sewed near the bottom: brass button riveted to the bottom of the box. Loop, two inches wide, placed upright on the back of the box for the waist-belt to pass through.

252. Pistol-Frog—buff leather—wide enough at the mouth to cover the cock of the pistol, and at the lower part to accommodate the stock; upper part of the back of it turned down to form a loop large enough to admit the waist-belt. The stitches forming the side seams not to come nearer than 0.25 inch from the edges of the leather. To be worn on right hip.

Pocket—thin bridle leather—to contain three cartridges; flap, tongue, and loop.

Cap-pocket, like the cartridge-pocket; lining, a strip of sheepskin with the wool on, glued with fish-glue and sewed to the back at the mouth of the pocket.

These two pockets are of the same depth, and occupy the whole breadth of the pistol-frog.

253. Thumbstalls, of buckskin, with hair-stuffed pad, and thongs for the wrist.

254. Musket Cartridge-Box—black bridle leather—length, 7.2 inches; width, 1.6 inch; depth in front, 5.8 inches; inner cover—upper leather—4 inches wide, with end pieces sewed to it so as to cover the ends of the box; flap—harness leather—8.5 inches wide at the bottom, 8 inches at top, stamped U.S.N. in an oval on the outside; a button-hole strap, sewed near the bottom; brass button riveted to the bottom of the box; loop—bridle leather—with a hole in the middle to hook the shoulder-belt to, sewed to the back of the box for the waist-belt to pass through.

Cap-pocket—light upper leather—sewed to the front of the box; length, 4 1/2; depth, 2 1/2 inches; flap, tongue, and loop—bridle leather; lining, a strip of sheepskin with the wool on, 1.5 inch wide, glued with fish-glue and sewed at the mouth of the pocket; pocket for ball-screw and wiper sewed on the right, and for cone-key and cone-pick on the left of the cap-pocket.

Two tin linings, each with a lower division, 3 inches by 3.3 inches, open in front, to contain a bundle of ten cartridges, and two bundles of caps containing 25 each, packed in water-proof paper. Each tin has also two upper divisions, 2.7 inches deep—one of 2 inches by 1.35 inch for six cartridges; the other, 1.35 inch square, for four cartridges. The edges of the tins are turned over and soldered down, to prevent them from cutting the fingers.

All the tin linings should be made to slide freely in the boxes.

255. Carbine Cartridge-Box.—The leather parts are like those of the musket cartridge-box; length, 6.4 inches; depth in front, 3.7 inches; width, 1.3 inch; inner cover, 3.5 inches wide; flap, 6.6 inches wide at top, 6.8 at bottom, 6 deep. Tin linings; two lower divisions, 2 inches deep, 2.9 inches long, 1.2 wide; five upper divisions, 1.2 inch wide by 1.15 inch long, and 1.5 inch deep, to contain forty cartridges, those below in bundles of water-proof paper.

256. Cone-Pick of steel wire, No. 18, 1.5 inch long, with a ring-handle 0.5 inch in diameter; it is carried, with the cone-key, in the pocket in front of the musket cartridge-box.

257. Bayonet Scabbard—black bridle leather—length, 19.3 inches. Frog—buff leather—sewed to a socket of black leather, which is fastened to the top of the scabbard; the loop of the frog to be made wide enough to slide on the waist-belt.

MARKING SMALL ARMS.

258. It is directed that hereafter all small arms, when passed by the Inspector, be stamped in the following manner:

MUSKETS, CARBINES, AND PISTOLS.

On the top of the barrel, near the breech, with an anchor; and, on the lock-plate, the letter P over the initials of the Inspector, thus: P./A.B.

REVOLVERS.

On the top of the barrel, near the cylinder, with an anchor; and, on the face of the cylinder, the letter P over the initials of the Inspector, as above.

CUTLASSES.

On the blade, immediately below the guard, with an anchor; and the letter P over the initials of the Inspector, as above.

All arms in store or returned from ships will be stamped with the anchor before being issued.

The Bureau will furnish to each Inspector two sizes of stamps. Muskets, Carbines, and Cutlasses are to be marked with the larger, .15-in., and Pistols and Revolvers with the smaller, 0.1-in., size of stamps.

PRESERVATION OF SMALL ARMS.

259. The Captain will take care that the Small Arms are carefully cleaned and wiped dry after every exercise or use of them, before they are put away.

260. He will cause them to be frequently examined at other times, to prevent their being clogged with oil or lacquer, and to be sure that they are always ready for use.

He will strictly prohibit their being marked or otherwise defaced.

261. It is directed that the men who use them be taught to clean them properly, and to remedy any slight defects or obstructions to their use.

Chests not lined preserve them best, if there be no proper armory.

DIRECTIONS FOR CLEANING ARMS.

262. In taking apart and cleaning guns, there are required a screw-driver, wiper, wire-tumbler punch, and a spring vice. No other implements should be used in taking arms apart, or in setting them up.

263. Dismounting and Cleaning.—The rifle-musket should be dismounted in the following order, viz.:

1st. Unfix the bayonet. 2d. Insert the tompion. 3d. Draw the ramrod. 4th. Turn out the tang-screw. 5th. Take off the lock; to do this, put the hammer at half-cock, and partially unscrew the side screws; then, with a slight tap on the head of each screw with a wooden instrument, loosen the lock from its bed in the stock; turn out the side screws, and remove the lock with the left hand. 6th. Remove the side screws without disturbing the washers. 7th. Take off the bands in order, commencing with the uppermost. 8th. Take out the barrel; in doing this, turn the musket horizontally, with the barrel downward, holding it loosely, with the left hand below the rear sight and the right hand grasping the stock by the handle; tap the muzzle on the ground, if necessary, to loosen the breech. If an attempt were made to pull the barrel out by the muzzle, it would, in case it were wood-bound, be liable to split at the head of the stock.

The foregoing parts of the rifle-musket are all that should usually be taken off or dismounted.

The breech-screw should be taken out only by an armorer, and never in ordinary cleaning. The mountings, cone and cone-seat screw, should not be taken off, nor should the lock be taken apart, except by permission of an officer.

264. To Clean the Barrel.—1st. Stop the vent with a peg of soft wood, or piece of rag or soft leather pressed down by the hammer; pour a gill of water, warm, if it can be had, into the muzzle; let it stand a short time to soften the deposit of powder; put a plug of soft wood into the muzzle and shake the water up and down the barrel; pour it out and repeat the washing until the water comes out clear; remove the peg from the cone and stand the barrel muzzle downward, to drain, for a few moments.

2d. Screw the wiper on the end of the ramrod, and put a piece of dry cloth or tow round it sufficient to prevent it from chafing the grooves of the barrel; wipe the barrel dry, changing the cloth two or three times.

3d. Do not put oil into the vent, as it will clog the passage and cause the first cap to miss fire; but, with a slightly oiled rag on the wiper, rub the bore of the barrel and the face of the breech-screw, and immediately insert the tompion into the muzzle.

4th. To clean the exterior of the barrel, lay it flat on a bench or board, to avoid bending it. The practice of supporting the barrel at each end, and rubbing it with a strap, buffstick, ramrod, or any other instrument to burnish it, is pernicious, and should be strictly forbidden.

5th. After firing, the barrel should always be washed as soon as practicable; when the water comes off clear, wipe the barrel dry and pass into it an oiled rag. Fine flour of emery cloth is the best article to clean the exterior of the barrel.

265. To Clean the Lock.—Wipe every part with a moist rag, and then a dry one; if any part of the interior shows rust, put a drop of oil on the point or end of a piece of soft wood dipped into flour of emery; rub out the rust and wipe the surface dry; then rub every part with a slightly oiled rag.

266. To Clean the Mountings.—For iron and steel parts, use fine emery moistened with oil, or emery cloth. For brass parts, use rotten-stone moistened with vinegar or water, applied with a rag, brush, or stick; oil or grease should be avoided. The dirt may be removed from the screw-holes by screwing a piece of soft wood into them. Wipe all parts with a linen rag, and leave the parts slightly oiled.

267. Dismounting by an Armorer.—The parts which are specially assigned to be dismounted by an experienced armorer will be stated in their regular order, following No. 8, viz.:

9th. Unscrew cone. 10th. Take out cone-seat screw, 11th. Take out band-springs, using a wire punch. 12th. Take out the guard-screws. Be careful that the screw-driver does not slip and mar the stock. 13th. Remove the guard without injuring the wood at either end of the plate. 14th. Remove the side screw-washers with a drift-punch. 15th. Remove the butt-plate. 16th. Remove the rear-sight. 17th. Turn out the breech-screw by means of a "breech screw-wrench" suited to the tenon of the screw. No other wrench should ever be used for this purpose, and the barrel should be held in clamps neatly fitting the breech.

268. Lock.—To take the lock apart: 1st. Cock the piece and apply the spring-piece to the mainspring; give the thumb-screw a turn sufficient to liberate the spring from the swivel and mainspring notch; remove the spring. 2d. The sear-spring screw. 3d. The sear-screw and sear. 4th. The bridle-screw and bridle. 5th. The tumbler-screw. 6th. The tumbler. This is driven out with a punch inserted in the screw-hole, which at the same time liberates the hammer. 7th. Detach the mainspring swivel from the tumbler with a drift-punch. 8th. Take out the feed-finger and spring. 9th. The catch-spring and screw.

269. As a general rule, all parts of the musket are assembled in the inverse order in which they are dismounted. Before replacing screws, oil them slightly with good sperm oil, as inferior oil is converted into a gum, which clogs the operation of the parts. Screws should not be turned in so hard as to make the parts bind. When a lock has, from any cause, become gummed with oil and dirt, it may be cleaned by boiling in soap-suds, or in pearlash or soda-water; heat should never be applied in any other way.

270. Precautions in Using.—In ordering arms on parade, let the butt be brought gently to the ground, especially if the ground be hard. This will save the mechanism of the lock from shocks, which are very injurious to it, and which tend to loosen and mar the screws and split the wood-work.

The ramrod should not be sprung with unnecessary force, for fear of injuring the corners of the grooves; and, in stacking arms, care should be taken not to injure the bayonets by forcibly straining the edges against each other.

No cutting, marking, or scraping the wood or iron should be allowed, and no part of the gun should be touched with a file. Take every possible care to prevent water from getting between the lock, or barrel and stock. If any should get there, dismount the gun as soon as possible, clean and oil the parts as directed, and see that they are perfectly dry before assembling them.

PAINTS AND LACQUERS.

COMPOSITION AND PREPARATION.

271. The proportions are given for 100 parts by weight of prepared colors, when not otherwise designated.

A gallon of linseed oil weighs	7.5 lbs.
A gallon of spirits of turpentine	7.25 lbs.
A gallon of Japan varnish	7. lbs.
A gallon of sperm oil	7.12 lbs.
A gallon of neatsfoot oil	7.63 lbs.

PAINTS AND LACQUERS.

Boiled oil.

Raw linseed	103. lbs.
Copperas	3.15 lbs.
Litharge	6.3 lbs.

Dryings.

Mixture of copperas and litharge taken from the boiled oil	60 lbs.
Spirits turpentine	56 lbs.
Boiled oil	2 lbs.

Putty (for filling cracks in wood).

Spanish whiting, pulverized	81 lbs.
Boiled oil	20.4 lbs.

Another kind of putty, for the same purpose, is made by mixing fine sifted oak sawdust with linseed oil which has been boiled till glutinous.

White paint.

	Proportions.
	For inside work.	For outside work.
White-lead, ground in oil	80. lbs.	80. lbs.
Boiled oil	14.5 lbs.	9 lbs.
Raw oil	0. lbs.	9 lbs.
Spirits turpentine	8. lbs.	4 lbs.

Grind the white-lead in the oil, and add the spirits of turpentine. New wood-work requires about 1 lb. to the square yard for three coats.

Lead color.

White-lead, ground in oil	75. lbs.
Lampblack	1 lb.
Boiled linseed oil	23. lbs.
Litharge	0.5 lb.
Japan varnish	0.5 lb.
Spirits turpentine	2.5 lbs.

The lampblack and litharge are ground separately upon the stone, in oil, then stirred into the white-lead and oil; the turpentine and varnish are added as the paint is required for use, or when it is packed in kegs for transportation.

Black paint.

Lampblack	28 lbs.
Litharge	1 lb.
Japan varnish	1 lb.
Linseed oil, boiled	73 lbs.
Spirits turpentine	1 lb.

Grind the lampblack in oil; mix it with the oil, then grind the litharge in oil and add it, stirring it well into the mixture. The varnish and turpentine are added last.

This paint is used for the iron-work of carriages.

Paint for tarpaulins.

A square yard takes 2 lbs. for three coats.

1. Olive.—	Liquid olive color	100 lbs.
	Beeswax	6 lbs.
	Spirits turpentine	6 lbs.

Dissolve the beeswax in the spirits of turpentine, with a gentle heat, and mix the paint warm.

2. Add 12 ounces of beeswax to a gallon of linseed oil, and boil it two hours; prime the cloth with this mixture, and use the same in place of boiled oil for mixing the paint. Give two coats of paint.

Lacquers for iron ordnance.

1. Black-lead, pulverized	12 lbs.
Red-lead	12 lbs.
Litharge	5 lbs.
Lampblack	5 lbs.
Linseed oil	66 lbs.

Boil it gently about twenty minutes, during which time it must be constantly stirred.

2. Umber, ground	3.75 lbs.
Gum-shellac, pulverized	3.75 lbs.
Ivory-black	3.75 lbs.
Litharge	3.75 lbs.
Linseed oil	78. lbs.
Spirits turpentine	7.25 lbs.

The oil must be first boiled half an hour. The mixture is then boiled twenty-four hours, poured off from the sediment, put in jugs and corked.

3. Coal tar of good quality	2 galls.
Spirits turpentine	1 pint.

The turpentine to be added in small quantities during the application of the lacquer.

4. Anti-corrosion	40 lbs.
Grant's black, ground in oil	4 lbs.
Red-lead, as a dryer	3 lbs.
Linseed oil	4 galls.
Spirits turpentine	1 pint.

This mixture, when well stirred and incorporated, will be fit for use; but, as by long keeping in this state it becomes hard, no more should be mixed than may be required for immediate use.

Anti-Corrosion.—	Slag from iron foundries, pounded	12 lbs.
	Chalk	12 lbs.
	Soot, common	1 lb.

In applying lacquer, the surface of the iron must be first cleaned with a scraper and a wire brush, if necessary, and the lacquer applied hot, in two thin coats, with a paint-brush. It is best done in summer.

Old lacquer should be removed with a scraper, or by scouring, and not by heating the guns or balls, by which the metal is injured.

PLANTOU'S COMPOSITION FOR COATING IRON OR WOOD AS A PRESERVATIVE.

First composition.

Pulverized rosin	3 lbs.
Pulverized shellac	2 oz.
Pulverized charcoal, or cannel-coal	1 lb.
Spirits turpentine	1 oz.

Second composition.

Pulverized rosin	3 lbs.
Beeswax	4 oz.
Pulverized charcoal, or cannel-coal	1 lb.
Spirits turpentine	1 oz.

The first two articles are to be dissolved in an iron vessel over the fire; the charcoal is then added, and briskly stirred until the whole is well intermixed; after which the turpentine is added, and stirred until it is well incorporated with the other ingredients. It is not safely made on board ship.

The composition is to be applied when hot, with a brush or spatula, and smoothed over with a hot iron. The wood, or iron should be perfectly dry, and freed from rust or other loose substances.

Lacquer for small arms, or for water-proof paper.

Beeswax	13 lbs.
Spirits turpentine	13 galls.
Boiled linseed oil	1 gall.

All the ingredients should be pure, and of the best quality. Heat them together in a copper or earthen vessel, over a gentle fire, in a water-bath, until they are well mixed.

Lacquer for bright iron-work.

Linseed oil, boiled	80.5 lbs.
Litharge	5.5 lbs.
White-lead, ground in oil	11.25 lbs.
Rosin, pulverized	2.75 lbs.

Add the litharge to the oil, let it simmer over a slow fire for three hours; strain it, and add the rosin and white-lead; keep it gently warmed, and stir it until the rosin is dissolved. Apply it with a paint-brush.

Varnish for scabbards, or patent leather.

For 1st and 2d coats.—	Prussian blue, in lumps	4. lbs.
	Sugar-of-lead	0.7 lb.
	Aquafortis	0.7 lb.
	Linseed oil, boiled	70. lbs.
	Spirits turpentine	24.6 lbs.

The ingredients, except the turpentine, are boiled together, in an iron kettle, eight hours, when the mixture will assume a brilliant black color. When the varnish is nearly cool, stir in the turpentine. The kettle in which the varnish is made should be of a capacity to hold double the quantity of varnish to be boiled. It cannot be safely made on board ship.

For the third or finishing coat.—Copal Varnish.

Gum-copal, in clear lumps	26.5 lbs.
Boiled linseed oil	42.5 lbs.
Spirits turpentine	31. lbs.

This varnish is made in a copper vessel, smallest at the top, in the form of a still.

Put the copal in the vessel, set it on a charcoal fire for one hour, in which time it will melt, and all the watery particles will evaporate. Add the oil whilst the copal is warm, but not boiling hot. When nearly cool add the turpentine, which will give it a proper consistency for use.

For 5 lbs. copal, and the proper proportions of oil and turpentine, the vessel should hold six gallons. Not safely made on board ship.

Japan varnish.

Litharge	4 lbs.
Boiled oil	87 lbs.
Spirits turpentine	2 lbs.
Red-lead	6 lbs.
Umber	1 lb.
Gum-shellac	8 lbs.
Sugar-of-lead	2 lbs.
White vitriol	1 lb.

Japan varnish is generally purchased from the paint-sellers. It is made by boiling on a slow charcoal fire for five hours all the ingredients except the turpentine and a small portion of the oil. The latter is added as required to check the ebullition and to allay the froth which rises to the surface. It must be continually stirred with a wooden spatula. Great care is necessary to prevent it from taking fire, and therefore it cannot be safely made on board ship.

The turpentine is added after the varnish is nearly cool, and is stirred well in. The varnish must be kept in tin cans closely corked.

Olive paste.

Yellow ochre, pulverized	68. lbs.
Lampblack	1.1 lbs.
Boiled oil	37. lbs.
Spirits turpentine	0.4 lb.

Make a thick paste with the ochre and oil in a paint-pot, and with the lampblack and oil in another. Grind them together in small portions, and keep the mixture in a tin vessel.

Liquid olive color.

Olive paste	61.5 lbs.
Boiled oil	29.5 lbs.
Spirits turpentine	5.5 lbs.
Dryings	3.5 lbs.
Japan varnish	2. lbs.

Stirred together in a paint-pot.

Brainard's paint.

Dissolve 10 pounds of shellac in 10 gallons of boiling water, adding 30 ounces of saleratus. Mix this solution with an equal quantity of paint prepared in the usual manner. This paint is economical and durable.

Black stain (for wood-work).

Copperas	1 lb.
Nutgalls	1 lb.
Sal ammoniac	1/4 lb.
Vinegar	1 gal.

Stir it occasionally for a few hours, and it will be ready for use.

The wood must be clean and smooth, and the cracks filled with black putty, which must be allowed to dry. The stain to be applied two or three times, and left to dry for a day or two. Then it is to be rubbed with boiled oil until sufficiently polished. Until the oil is applied the color will be bluish. Scraping and staining gun-carriages, or keeping them bright, is prohibited. They should be kept well painted.

Impression wax for vents.

Beeswax	4 parts.
Tallow	2 parts.
Charcoal, finely powdered	1 part.

Melt the beeswax and tallow, and stir in the charcoal.

Paper parchment.

Immerse unsized paper for a few seconds in sulphuric acid, diluted with half its volume of water at about 60°; wash it well in cold water, then immerse it in a weak solution of caustic ammonia, and again wash.

It absorbs water, and becomes soft and pliable like animal parchment, but is water-proof. It is not affected by boiling water, is indestructible by most acids, and is not diminished in strength by wetting. It has about 2/3 the strength of animal parchment when dry; the thinner kinds make capital tracing-paper, which takes ink readily.

Cement for the above.

Cheese—fresh, without salt, if possible	3 parts.
Quicklime	1 part.

Wash the cheese thoroughly three or four times in boiling water, and grind the materials on a stone and muller, adding cold water until it is of the consistency of honey.

Composition for lining the interior of rifle-shells.

Soap—common yellow, not salt-water soap	3 parts.
Tallow	7 parts.
Rosin	7 parts.

The tallow should be melted first, then melt and add the rosin, and lastly the soap, bringing the mass to a heat that will make it very fluid.

The shells having been first thoroughly cleaned, fill them about one-third full of the composition, roll them slowly so as to spread the mixture over the whole interior surface, and then pour off the residue. This coating should be about one-tenth (0.1) of an inch in thickness, except at the bottom of the shell, where it should be about three-quarters of an inch thick. To obtain these thicknesses, the operation of coating should be performed twice; then pour into the shell enough of the composition to produce the desired thickness at the bottom, the shell standing on its base. After the composition is perfectly cool, immerse the shell in hot water at as high a temperature as the composition will stand without "running"—about 170 degrees. This second heating of the composition in the bath toughens it, and causes it to adhere more closely to the shell.

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