French Ordnance.

A = Over all.
B = Bore.
C = Number of Grooves.

Name, Nature, and Classification.	Calibre.	Length.		C
Name, Nature, and Classification.	Calibre.	A	B	C
	In.	In.	In.
French pattern, cast-iron, steel-lined Breech-loaders.
Model of 1870.
32 cm.	12.6	264	244	32
27 ”	10.8	212	194	28
24 ”	9.46	195	179	24
19 ”	7.64	164	151	20
16 ”	6.49	146	135	16
14 ”	5.46	123	115	14
Model of 1864-67.
27 ”	10.8	184	167	5
24 ”	9.46	180	165	5
19 ”	7.64	150	138	5
16 ”	6.49	133	124	3
14 ”	5.46	81	73.6	3
Bronze Muzzle-loaders
12 cm	4.78	81.4	71.5	6
4 ”	3.41	37.8	31.7	6
Hotchkiss Machine-gun.	1.46	51.2	29.1
Model of 1858-60 Muzzle-loaders
22 cm
16 ”
14 ”

D = Twist of Rifling.
E = Gun, including Breech-block.
F = Breech-block.
G = Preponderance.

Name, Nature, and Classification.	D	Weight.		G
Name, Nature, and Classification.	D	E	F	G
	Cal.	Lbs.	Lbs.	Lbs.
French pattern, cast-iron, steel-lined Breech-loaders.
Model of 1870.
32 cm.	0/45	85,800	1,540	396
27 ”	0/45	51,040	1,100	88
24 ”	0/45	34,400	726	88
19 ”	0/45	17,500	352	88
16 ”	0/30	12,000		103
14 ”	0/30	5,900	176	103
Model of 1864-67.
27 ”	0/30	45,100	704
24 ”	0/30	31,900	567
19 ”	0/30	17,610	295
16 ”	0/30	11,000	191	330
14 ”	0/30	4,100	103	165
Bronze Muzzle-loaders.
12 cm.		1,360		176
4 ”		220		33
Hotchkiss Machine-gun.		440
Model of 1858-60 Muzzle-loaders.
16 ”
14 ”

A = Carriage.
B = Slide.
C = Steel.
D = Chilled.
E = Common.
F = Canister.
G = Bursting Charge Common Shell.

Name, Nature, and Classification.	Carriage.		Projectiles.
	Weight.		Complete Weight.				Weight.
	A	B	C	D	E	F	G
	Lbs.	Lbs.	Lbs.	Lbs.	Lbs.	Lbs.	Lbs.
French pattern, cast-iron, steel-lined Breech-loaders.
Model of 1870.
32 cm.			770	770	630		37.4
27 ”	10,230	12,960	475	475	396	317	24
24 ”	7,304	8,140	317	317	264	220	17
24 ”	5,720	8,140	317	317	264	220	17
19 ”	4,664	11,550	165	165	137.5	114	7
19 ”	4,400	3,410	165	165	137.5	114	7
16 ”	3,520	9,460	99	99	84	69
14 ”	2,085>	1,287			46	41	2.4
Model of 1864-67.
27 ”	10,230	12,980		475	317	321	14.6
24 ”	5,720	8,140		817	220	211	10.3
24 ”	5,720	8,140		817	220	220	10.3
19 ”	4,400	3,410		165	115	105	4.8
16 ”	3,520	9,460		99	69	66	3
16 ”	2,639	1,260		99	69	66	3
14 ”	1,540	1,100			41	27	2.1
14 ”	1,540	1,100			41	39.6	2.1
Bronze Muzzle-loaders.
12 cm.	1,023				25	24.6	1.1
12 cm.	385				25	24.6	1.1
4 ”	352	231			10	10	.17
4 ”	319	231			10	10	.17
Hotchkiss Machine-gun.
Model of 1858-60 Muzzle-loaders.
22 cm.
16 ”
14 ”

A = Steel and Chilled Shot.
B = Common Shell.
C = Ordinary.
D = Saluting.
E = Steel.
F = Chilled.
G = Common.

Name, Nature, and Classification.	Powder Charge.				Initial Velocity.
Name, Nature, and Classification.	A	B	C	D	E	F	G
	Lbs.	Lbs.	Lbs.	Lbs.	Feet.	Feet.	Feet.
French pattern, cast-iron, steel-lined Breech-loaders.
Model of 1870.
32 cm.	132	132			1,394	1,394	1,496
27 ”	92.4	92.4	52.8	19.8	1,417	1,417	1,542
24 ”	61.6	61.6	35.2	13.2	1,443	1,443	1,555
19 ”	33	33	17.6	7.7	1,456	1,456	1,726
16 ”	20.9	20.9			1,575	1,575	1,660
14 ”		9	9	3.3			1,493
Model of 1864-67.
27 ”	79.2	52.8	52.8	19.8		1,086	1,188
24 ”	52.8	35.2	35.2	13.2		1,115	1,188
19 ”	27.5	17.6	17.6	7.7		1,128	1,168
16 ”	16.5	11	11	5.5		1,132	1,197
14 ”		4.4	4.4	4.4			1,053
Bronze Muzzle-loaders.
12 cm.		2.2	2.2	2.2			1,007
4 ”		.66	.66	.66			738
Hotchkiss Machine-gun.	.18						1,318
Model of 1858-60 Muzzle-loaders.
22 cm.
16 ”
14 ”

Name, Nature, and Classification.	Muzzle Energy			Penetration.
Name, Nature, and Classification.	Steel.	Chilled.	Common.	Steel.	Chilled.
	Ft. Tons.	Ft. Tons.	Ft. Tons.	In.	In.
French pattern, cast-iron, steel-lined Breech-loaders.
Model of 1870.
32 cm.	10,390	10,390	9,730	14.5	14.5
27 ”	6,596	6,596	6,506	12.5	12.5
24 ”	4,561	4,561	4,414	11.1	11.1
19 ”	2,330	2,330	1,828	9	9
16 ”	1,698	1,698	1,598	8.2	8.2
14 ”			712
Model of 1864-67.
27 ”		3,871	3,088		9.6
24 ”		2,821	2,144		8.75
19 ”		1,451	1,081		7.0
16 ”		876	687		5.87
14 ”			314
Bronze Muzzle-loaders.
12 cm.			176
4 ”			39		.94
Hotchkiss Machine-gun.					.94
Model of 1858-60 Muzzle-loaders.
22 cm.
16 ”
14 ”

GUNS.

Smooth-bore guns are entirely obsolete, except for saluting purposes at dock-yards.

The rifled ordnance consists of the cast-iron breech-loader, model 1870, the cast-iron breech-loader, model 1864-67, the cast-iron muzzle-loader, model 1858-60, the bronze muzzle-loader, the mitrailleuse, and the Hotchkiss machine-gun. A new all-steel pattern is being introduced into the service, whose attachments are quite similar to the model of 1870.

The two models of breech-loaders differ radically in the style of rifling, and although the breech mechanism is the same in principle in both types, it is quite different in detail.

Breech-Loader, Model 1870.

Guns of this type consist of a cast-iron body strengthened by a steel tube and steel hoops. The steel tube, which is about one quarter of a calibre in thickness, is inserted into the bore from the rear, and is set fast by a heavy male screw-thread worked at its rear end. It extends a short distance forward of the trunnions. The steel hoops are shrunk on over the cast-iron body, and cover all that part occupied by the tube. For the 14-cm. calibre there is but one row of hoops; for the higher calibres two rows breaking joints. The trunnions form a part of the hoop next to the forward one. In all calibres above 16-cm. this trunnion-hoop is thicker than the others, and forms a salient on the surface of the gun.

27-cm. French Gun, Model 1870.

The bore is rifled on the multigroove system, with an increasing twist of from 0° at the breech to 4° at the muzzle, the direction of the twist being from right to left (contrary to the invariable rule in other countries). The chamber proper is divided into four parts: the shot-chamber, the powder-chamber, the gas-check seat, and the breech-block seat.

The shot-chamber is conical in shape, small end forward, the rifling vanishing at this point in an easy slope. The diameter of this end is the same as that of the bore measured across the grooves. The rear end is joined to the powder-chamber by a second small cone, against which the rear ring of the projectile takes when home.

The powder-chamber is cylindrical, and of a diameter slightly greater than that of the bore.

The gas-check seat is of considerably greater diameter than the powder-chamber. It is conical in shape, small end forward.

Breech-Block (Gun open).

Breech-Block (Gun closed).

The breech-block seat is cylindrical, having a heavy screw-thread around its wall, which is cut into three equal sectors, leaving three blanks of the same width. One of these blanks comes at the bottom of the seat, in order to allow the breech-block to slide back and forth.

The breech mechanism consists of two main parts, the block and the console or bracket, which is hinged to the face of the breech and holds the block when it is withdrawn from its seat.

Gas-Check (1871).

The breech-block is a steel cylinder having heavy screw-sectors about its surface to correspond with those in the seat. The last turn of screw-thread is left entire in order to relieve the shock of closing the breech. The forward face is made movable in order that when it becomes worn and scored by the action of the powder-gas it may be changed. This face is a steel disc which sets flat against the face of the block, and is of the same diameter. It seats in the face of the block by means of a smaller cylinder or trunnion, and projecting from the rear of this trunnion is a steel rod, which passes completely through the axis of the block and carries the vent. In order to prevent the disc from having any independent motion, a small tenon on its rear face enters a socket in the face of the block. The disc is keyed fast by a small pin which is screwed radially through the block near the middle, the end of the pin taking in a score cut in the vent-rod. A small catch, projecting from the rear lower side of the block, holds the console in place when the breech is closed. The rear face of the block is provided with two parallel handles screwed to it, to assist in moving it, and a long crank-handle between them for revolving the block. At the end of this crank-handle there is a slight projection made to receive the blows of any instrument that may be used to drive the block around when it works stiffly. Along the two lower blanks of the block slots are cut, in which traverse small projections of the console to hold the block steady. About the middle of the lower screw-sector a small hole is cut into which a small stop springs when the block is withdrawn to its limit on the console. The vent is provided with a copper bush at its forward end and a steel one at its rear.

The console is semi-cylindrical, and is hinged to the face of the breech so that when the breech-block is withdrawn it may be swung to the right and unmask the bore. It is provided with a spring stop and two small projections taking in the block, which limit the movement of the latter and hold it steady when resting on the console.

Two small pins, screwed into the face of the breech, limit the arc of movement of the crank-handle, one at the vertical point and the other 60° to the right.

A small stop attached to the face of the breech holds the crank-handle fast when the breech is closed. This stop allows the handle to pass in closing, but must be raised by hand in opening.

The gas-check is of copper, and is a fixture in its seat. It is a ring in reality, the centre being cut out to permit the passage of the charge through it in loading; the edge is turned up, forming a cup, the outer part being conical to fit the seat. The bend of the rim is quite thick, and a gutter is cut around it in order to make the powder-gas seal the joint properly. The bottom of this ring is provided with three concentric grooves to break the force of the gas that may escape through the joints. When the breech is closed the face of the block presses directly on the gas-check, and a copper ring is countersunk in the face of the block which forms the contact with the check. This ring has grooves to correspond with the grooves on the back of the gas-check.

The vent is horizontal, and is situated in the axis of the breech-block. Its outer end is formed in double-cone shape (throughout the steel bush), the small ends of the cone being joined. Percussion primers are used in connection with a spring gun-lock. ([See Primers].)

Breech-Loader, Model 1864-67.

These guns are hooped like the model of 1870, but are not tubed.

14-cm. French Gun.

The vent is pierced vertically near the bottom of the powder-chamber, instead of being in the breech-block.

The grooves are of the pattern known as the “basket-handle,” for mechanical fit projectiles ([see French Groove, English Ordnance]), having an increasing twist of from 0° to 6°. The 14-cm. and 16-cm. guns have three grooves, the others five. The width of the grooves is the same throughout the length of the bore, being cut back on the loading side near the powder-chamber to facilitate loading. The depth of the groove, however, diminishes towards the muzzle in order to pinch the studs and steady the projectile. At the powder-chamber and running forward for a short distance in the centre of each band is a supplementary groove, in which travel the rear studs of the projectiles, which are made so small as to easily sheer off. These secondary grooves prevent the projectile from being pushed too far into the bore. With the 19-cm. gun, the supplementary groove is made by cutting back the loading side of the regular groove. There is no shot-chamber proper.

Groove (1864).

Groove (1871).

Rear end of Groove (1864),
showing Stop for Projectile.

The powder-chamber is cylindrical, of the same diameter as that of the bore across the grooves. The bottom groove is produced through the powder-chamber, to serve as a directing groove for the projectile in loading.

In rear of the powder-chamber there are two gas-check seats, conical in shape, with the small diameter forward. The rear and larger one is intended for service in case of accident to the other.

Gas-Check (1864).

Breech-Block (Section).

The breech-plug seat is similar to the model 1870.

The breech-closing mechanism consists of two main parts like that of the model 1870, the breech-plug and the console or bracket.

The breech-plug differs from the model 1870 in being lighter, by having the interior cut away as much as possible consistent with strength. It has two movable faces or discs to correspond with the two gas-check seats. These discs are secured to the face of the plug in a similar manner to the model 1870, except that the disc in this case is allowed to revolve freely. The gas-check is carried on the face of the disc instead of being a fixture of the gun.

It is quite similar to the model 1870, except that the hole in the centre is smaller and serves to secure it to the face of the disc. The centre of the disc being slightly raised carries two ears which receive the inner edge of the gas-check and centre it. Over these a solid-headed nut screws, which fixes the gas-check and makes a tight joint. The gas-check is made of steel.

The console is similar to the model 1870.

Muzzle-Loader, Model 1858-60.

These guns are hooped, but have no tubes. The trunnions are cast with the body of the gun, the hoops not coming so far forward. The vent is vertical near the bottom of the powder-chamber, like the model 1864.

The grooves are of the “basket-handle” type, three in number, with an increasing twist of from 0° to 6°. These grooves, near the chamber, are cut back and prolonged to form seats for the rear studs.

All guns of this model are converted from old smooth-bores.

Bronze Muzzle-Loader.

These guns are of the ordinary bronze type. The 23-pdr. (canon de 12) has six common grooves having a regular twist from left to right. The bottom groove is narrowed on the loading side near the powder-chamber in order to force the studs into close contact with the driving side. The 8-pdr. (canon de 4) has six grooves with a regular twist similar to the 23-pdr.

The vent is pierced vertically near the bottom of the powder-chamber.

The Mitrailleuse.

The exterior of the mitrailleuse has the appearance of a bronze cannon. This case encloses 25 rifled tubes brazed together. The rear part of the cannon presents a vertical cavity, very large and nearly rectangular in shape. This cavity is called the cage, and is intended to receive the breech-block and firing mechanism. The breech-block is a cubical block containing prolongations of the 25 barrels which serve as chambers for the cartridges. When loaded, this block drops into the forward part of the cage. The lock mechanism is a box containing 25 firing-pins, arranged with guides and springs on the ordinary system. This box is movable longitudinally by the motion of a breech-screw, which also sets up the breech-block when in place. The motion forward of this box retracts the firing-pins, which are then held until released in rapid succession by a turn of the crank. After firing, the breech-screw is backed, the block taken out and a loaded one is put in its place, the screw is set up retracting the locks, and the piece is ready for firing again.

Hotchkiss Machine-Gun.

([See United States Ordnance].) This gun is an American invention, but was first introduced into the French Navy.

CARRIAGES.

Gun-carriages in the French Navy are classified as follows:

Slide-carriages for heavy broadside-guns.

Turret-carriages and revolving-slide carriages for heavy guns.

Directing-bar carriages for broadside-guns.

Four-truck and rear-chock carriages for broadside-guns.

Gun-boat carriages for bronze guns.

Boat-carriages for bronze guns.

Mountain carriages for bronze guns.

Mitrailleuse saddle or fork for machine-guns.

Slide-Carriage for 27-cm. and 24-cm. Guns.

Elevating-Gear and Compressor,
24-cm. Gun.

The rails of the slide are of heavy double T iron, connected by T and plate iron transoms. The slide rests on a pair of conical rollers, with concentric axles forward and a double pair of rear rollers (concentric) at the rear. The forward pair of the rear rollers and the front rollers travel on smooth tracks, while the rear pair of rollers are pinions working in a rack on deck. The slide is traversed by tackles, except in fine pointing, when levers are shipped on the rear rollers and the fine traversing is done by heaving on them. A pawl working on the rear rollers secures the slide in any desired position. The recoil is checked by friction compressors. There are eight iron compressor-bars on each side of the slide, just inside of the rails, resting on the front and rear transoms. On top of the front transom is a heavy iron dumb-sheave, which receives the bight of a rope breeching. The carriage is of the ordinary form of double plate, mounted on rollers, the forward pair being in permanent action and the rear pair on eccentric axles. Tackles are used for running out and in. The compressor-plates are nine in number on each side, suspended on an axle. The outer plates are heavier than the others. The ones next to the brackets are backed by steel disc-springs. Rocking levers working in screw-threads on the axle press against the inner plates. The levers are worked by a ratchet-lever on the exterior right side, this lever being provided with a trip for throwing it down automatically in firing. Railway buffers are placed at the rear of the slide to act in case of over-recoil. The elevating-gear consists of a flat-linked chain passing underneath and supporting the breech of the gun. The ends of the chain wind about axles in the carriage-brackets, the axles being revolved by endless-screw gearing. Levers for turning this gearing ship outside the brackets. In elevating or depressing, it is necessary to turn the gearing alike on both sides in order to keep the centre link, which is marked, in its place under the breech. In elevating, the gearing must be worked slowly in order to allow the breech to follow down by its preponderance. With the 24-cm. gun, the compressor-plates, 12 in number, are all in the centre instead of being at the sides.

Slide-Truck
for 19-cm.
Gun.

Slide-Carriage for 19-cm. Gun.

The fixtures for the slide and carriage differ in several particulars from the heavier ones. The slide travels on four pairs of rollers, the rear rollers of the rear pairs being cogged for fine pointing as in the heavier ones. The slide rests on iron pillars with screw-threads at the upper extremities, the lower ones resting on the axles between the rollers, forming a pair. The threaded top has a capstan-head, so that, by turning, the front or rear of the slide may be elevated or depressed. These rollers are also arranged for transporting the slide from port to port. For this they may be turned to run in the desired direction, similar to the principle of chair-rollers (casters). Clamps are provided to hold them in the desired position.

The carriage has only one in-tackle. The rocking-lever compressor is changed to the ordinary bow-compressor. ([See English Ordnance], Compressor for wooden-slide carriages.)

Turret-Carriage and Slide for Heavy Guns.[7]

Additional Gearing for
Elevating-Gear of
Turret-Carriage.

The turret-slide, instead of being provided with rollers for traversing, is mounted on a centre-pivoting turn-table. The turret itself is fixed, the gun firing over it “en barbette.” The turn-table is mounted on sixteen conical rollers, and is revolved by means of a fixed rack, to which gears a pinion worked by a crank attachment on the slide. This attachment consists of a horizontal axle revolving in bearings through the rear of the slide-plates, having a crank at each end and a chain-wheel in the middle. An endless chain transmits the motion to gearing at the forward end of the slide, which connects with the rack on the floor of the turret. A locking arrangement holds the turn-table in the desired direction. The slide resting on its supports rises to a much greater height than with broadside-carriages, and is provided with a short stairway from the turn-table to the slide-top. The carriage is similar to the ones heretofore described, except that extra gearing is applied to the elevating apparatus to enable it to be reached by the men standing on the turn-table. Chain-gear similar to Scott’s in and out gear is used with the carriage. Instead of a movable stirrup used to catch the chain, the upper part passes through a slit in the rear transom of the carriage, so that when the rear trucks are thrown in action teeth in it catch the chain. The same style of compressor is used as is found with the 24-cm. carriage previously described, except for the 19 cm. gun, which has the ordinary cramp-compressor.

Barbette Turret-Carriage.

Revolving-Slide Carriage.

The slide is a centre-pivot resting on a circular track and on four rollers. It is traversed by a crank revolving gearing which works in a circular rack around the outside of the roller-circle. The carriage is similar to the ordinary type, except that it is much higher, in order to allow a greater angle of depression to the gun. Instead of in and out tackles, a runner is used which passes over a windlass fixed on the rear slide-transom. This runner throws the rear trucks in action, and then, according to its lead, runs the gun in or out. The elevating-gear for the 16-cm. gun consists of a heavy cross-bar underneath the breech, having sleeves at the extremities which clasp heavy upright screws. By revolving these screws, the bar is carried up or down. The elevating-gear for the 14-cm. gun is the old-fashioned telescopic elevating-screw.

Training-Gear for
Centre-Pivot.

Elevating-Gear for
Centre-Pivot Carriage.

Directing-Bar Carriage.

The carriage proper is of the ordinary rear-chock or Marsilly type, which when run out for firing is lifted from the deck on a slide or chariot, so that it may be easily and quickly trained. The chariot consists of a broad, short front-piece, mounted on two rollers; projecting forward from it is a pivot-flap which secures by a pivot-bolt just underneath the port, the rollers being canted for traversing about the pivot. Projecting to the rear from this front-piece is a tongue made of T iron, which is supported at its rear end on two trucks which are canted like the forward ones for traversing. When the carriage is run in, its rear end comes flush with the end of this tongue, and the forward trucks rest on the deck. In running out, however, two small rollers on the axle, inside of the brackets, catch on and mount two inclined planes which slope back from the top rear of the chariot, thus lifting the carriage completely from the deck. A breeching is used with this carriage, its bight going around a B block on the front of the chariot. There is also a friction compressor at the rear of the brackets, the compressor plates taking against the sides of the T iron, which are filled out with wood for that purpose. The forward edge of the B block serves as a hurter in running out. In all other respects the carriage is similar to the ordinary broadside rear-chock carriage. It is used on upper decks of large ships for light guns.

Four-Truck Carriage and Rear-Chock Carriage.

These are of the general type of old-fashioned wooden carriages.

Gun-Boat Carriages and Boat-Carriages.

These carriages are of the old-fashioned type. The former is the slide pattern, its only peculiarity being that its forward and rear rollers can be revolved for transportation on a vertical pivot. The carriage has no rear trucks.

Directing-Bar Carriage.

Boat-Carriage.

The carriage is provided with holding-down clips, and the recoil is checked by a breeching whose ends are made fast to the brackets, the bight passing around a bollard on the forward transom of the slide.

Mountain-Carriage.

The mountain-carriage is similar to the English field-carriage except the elevating-gear, which consists of a plain elevating-screw to which a hand-wheel and pinion gear.

Mitrailleuse Saddle.

This consists of a pillar whose lower end ships in a socket in the ship’s rail, and whose upper end branches into a fork to support the trunnions. A longitudinal support projects from the pillar, which holds a pivoted arm by means of a clamp. This gives a quick motion for elevating or depressing. The end of the pivoted arm holds an ordinary elevating-screw for slow motion.

Hotchkiss Saddle.

[See United States Gun-Carriages].

GUNPOWDER.

The gunpowder used in the French service is classified according to the size of grain.

Wetteren powder, named from the place of manufacture in Belgium, is a large-grained cubical powder used in guns of the model 1870.

Ripault powder, named from its place of manufacture in France, is an ordinary-sized cannon powder used in all guns, except the above.

Hunting powder is a small-grained, highly-glazed powder used in revolver cartridges.

B powder, of a slightly larger grain than the hunting, is used in Chassepot rifle cartridges.

Musket powder is used in the manufacture of primers, fuses, and signals.

CARTRIDGES.

Cartridge-bags are made either of parchment or serge. For the smaller calibres they are of parchment.

Each cartridge is marked in black with the calibre of the gun for which it is intended, the weight of charge, monogram of the place where it was filled, and date of filling.

Cartridges are kept aboard ship in brass or copper tanks of various forms having water-tight covers.

PROJECTILES.

The projectiles used in the French Navy are shot, shell and case-shot. There are two kinds of shot, cylindrical and ogivo-cylindrical, corresponding to the shape of the head; the cylindrical being used only in the calibres above 19 cm. They are all steel. The ogivo-cylindrical shot are used in all calibres above 14 cm., and are either of steel or chilled cast-iron. Shell are of cast-iron, and are similar in shape to the ogival shot.

Projectiles, Model 1864.

Armor-Shot.

Shell.

Solid Shot.

Projectiles, Model 1870.

Armor-Shot.

Shell.

Solid Shot.

These projectiles are differently mounted for the different models. For the model 1870 the mounting consists of a forward ring of zinc or cast-iron just back of the shoulder of the shell, slightly smaller than the diameter of the bore across the lands. Its object is simply to keep the forward end of the projectile centred. A rear ring of copper, of a diameter slightly greater than that of the bore across the grooves. This ring brings up in its seat in the shot-chamber, and on firing the bands are scored and rotate the projectile. Around the surface of this ring are two or three grooves, cut to receive the metal displaced by the lands on firing. These projectiles carry at their base a light wire grommet to facilitate handling them.

For the model 1864-67 the projectiles are provided with studs, there being two rows. The forward studs take in the grooves and give the twist to the projectile; the rear ones hold the base of the projectile centred, and according to the calibre of the piece they travel in the grooves or on the lands. For the heavy projectiles, where the rear studs travel on the lands, there are provided three small intermediate studs which bring up in false grooves provided for the purpose, keeping the projectile from going too far forward in the bore when loading. These studs are sheared off on firing. The studs are made either of zinc or bronze. Projectiles for the bronze muzzle-loaders are similar to the model 1864.

Case-shot are of the ordinary type, and have neither studs nor belts.

Sea-weed wads are used with all projectiles except those of the model 1870. These are used in order that the powder-charge may act with a more gradual effect on the projectile at the start. Placed between the charge and the projectile, their rapid compression gives room for the powder to expand and burn more slowly at the first instant.

FUSES.

Percussion fuses are used in all shell except the 25-pdr. and 8-pdr. boat-guns, which use time-fuses.

The percussion fuse consists of a hollow cylindrical bronze body having a solid conical head. At the bottom of the cylinder is screwed a copper firing-pin. The centre of the cylinder is occupied by a brass plunger carrying a charge of hunting powder. The forward end of this plunger carries a wooden plug which is hollow and filled with detonating composition. The plunger is held in position by two iron pins upon which the base rests, and two leaden stops through the wall of the fuse entering the shell of the plunger. These stops are not broken by the start of the projectile, but by its shock on striking an object. The bottom of the fuse, being covered by shellac-paper, is blown away by the charge of powder in the plunger, and the flame is communicated to the charge.

Percussion Fuse.

Time-Fuse.

The time-fuse for boat-guns consists of a brass body having two longitudinal chambers for fuse-composition columns of different times of burning. For the 23-pdr. the times correspond to 1500 and 3000 metres; for the 8-pdr. they correspond to 1100 and 2200 metres. The longer column is always uncapped on loading. The different times are distinguishable by the difference in the caps. That for the long time is of wire; for the short time it is of leather covered with a red wafer.

PRIMERS.

The primers are of two kinds, percussion and friction. The former seal the vent entirely on firing, and are only used in guns having vents through the breech-block (Model 1870). Friction primers are used in all guns having vertical vents.

The percussion primer consists of a body of brass or copper, slightly conical and having a solid head. Into this body screws a small steel anvil carrying an ordinary percussion-cap, which, when the anvil is screwed home, bears against the primer-head. The remainder of the body is filled with fine hunting powder, and the bottom is closed by a shellacked wafer.

Quill Primer.

Percussion Primer.

The friction primer consists of two quill tubes, the lower and larger one being filled with fine musket powder, the bottom being sealed with wax. The upper is filled with fulminating composition, and has passing through its centre a brass friction-wire corrugated along its length. The exterior of the wire is formed in a loop for hooking on the firing laniard. The upper part of the primer is closed by a block of wood forming a fairleader for the friction-wire. A small independent loop is attached to the head of the primer, by which it may be withdrawn from the vent without touching the friction-wire.

SIGHTS.

The sights used in the French Navy are all side-sights, and for the most part the tangent-sights are inclined at a permanent angle.

The front-sights are conical in shape, and are screwed into the rim-bases.

The tangent-sights are square in section, working in boxes screwed to the face of the breech. They are graduated to full and half cable-lengths (200 and 100 metres). As a rule, guns are sighted on the left side, although provision is made for a right tangent and front sight. Sights are graduated on the left side for shell and on the right for shot, the graduations being all carried across the rear face. In general there is a short and a long sight, the long one being used for distances greater than 30 cables (6000 metres).

ACCESSORIES.

The loading-plate is a plate which attaches to the breech of the gun when the breech-block is open; along the bottom of this plate is a groove which forms a prolongation of the bottom groove of the gun (not applicable to model 1870); the projectile being hoisted to the level of the bore is landed on this plate, and is then in position to be rammed home. For small projectiles this plate serves as a shell-bearer for transporting projectiles, being provided with side handles.

The shell is brought to the loading-plate on covered decks by means of a tackle appended to a roller working on a traveller. The projectile being hoisted from the deck is pushed along on the traveller to the plate. In turrets the projectile is hoisted and swung by means of a davit.

The passing-box for the cartridge is made of leather with an ordinary close leather cover.

The rammer and sponge are of the old-fashioned type.

In calibres of a nature above 16-cm. a leather guard is always used in loading, to cover the gas-check and prevent injury from shocks in loading.

A system of guards against firing the gun before the breech-block is entirely closed is attached to the breech or the breech-block. In guns of the model 1864 the guard consists of a small hollow cylinder with funnel-shaped ends, acting as a sort of fairleader for the firing laniard. On the laniard itself are worked three turk’s-heads which, when the laniard is rove through the fairleader and hooked to the primer, come forward of the forward edge. A small spring is attached to the closing-stop of the handle, which projects into the funnel and will not permit the laniard to pass. When the breech is closed, the crank pressing against the closing-stop pushes back the spring and allows a free passage to the laniard. In guns of the model 1870 the guard consists of a small disc which slides over the vent when the breech-block is opened, and remains there so that a primer cannot be inserted until the block is closed and locked.