XXVIII.

Tunnels on a level, the length of which do not exceed a third of a mile, will probably not be objectionable. Tunnels of equal length upon acclivities would be more objectionable.

I may observe generally that we have as yet little or no experience of the effect of tunnels on lines of railroad worked by locomotive engines, where there is a large intercourse of passengers. On the Leicester and Swannington railroad, there is a tunnel of about a mile long, on a part of the road which is nearly level; it is ventilated by eight shafts, and I have frequently passed through it with a locomotive engine. Even when shut up in a close carriage the annoyance is very great, and such as would never be tolerated on a line of road having a large intercourse in passengers. This railroad is chiefly used to take coals from some collieries near Swannington, and there is no intercourse in passengers upon it, except of the labouring classes from the adjacent villages: the engines burn coal, and not coke; and they consequently produce smoke, which is more disagreeable than the gases which result from the combustion of coke. This tunnel also is of small calibre.

On the Leeds and Selby railroad there is a tunnel, on a part which is nearly level, the length of which is 700 yards, width 22 feet, height 17. It is ventilated by three shafts of about 10 feet diameter and 60 feet high. There is an intercourse of passengers amounting to four hundred per day, upon this road, and, generally speaking, they do not object to go through the tunnel with a locomotive engine. The fuel is coke.

(l) In order to show the present state of railroad transportation in the United States, and enable our readers to compare it with the opinions and facts adduced by Dr. Lardner, we take the latest accounts from the Charleston and Hamburgh Railroad. The engines drag a train of cars which carry a load of 130 tons, and perform the distance (240 miles) in three days, travelling only by day-light. With these loads they mount planes having inclinations of 37 feet per mile. The same engines are capable of carrying passengers at the rate of 40 miles per hour, and often perform 30, but their average speed is limited by regulation to 20 miles per hour.

This railroad is remarkable for being the largest which has yet been constructed, and is besides an object of just pride, in as much as it was commenced at a time, when according to Dr. Lardner, the subject was but imperfectly understood even in Europe, and all its arrangements are due to native talent and skill, unassisted by previous discoveries in Europe.—A. E.

INDEX.

Atmospheric air, elastic force of, [23]

Atmospheric pressure rendered available as a mechanic agent by Denis Papin, [48]

Atmospheric engine, first conception of by Newcomen, [61].
Description of, [63].
Advantage of over that of Savery, [69]

Barometer, the, [21]

Barometer gauge, the, [123]

Belidor, [133]

Birmingham and London railroad, probable advantages to be derived from, [206]

Black, Dr., his doctrine of latent heat, [76]

Blasco de Garay, his contrivance to propel vessels, [42]

Blinkensop, Mr., constructs a locomotive engine, [161]

Boiler, methods for showing the level of water in the, [118.]
Its power and proportions, [297]

Bolton, Matthew, his connexion with Watt, [88]

—— and Watt, Messrs., immense expenditure of, in bringing their engines into use, [91]

Booth, Mr., his method of using tubes to conduct heated air through locomotive boilers, [176].
His report to the directors of the Liverpool and Manchester railway on the apparent discrepancies of Messrs. Walker and Rastrick's estimate of locomotive power, [189]

Braithwaite and Ericsson, Messrs., their "Novelty" described, [175]

Branca, Giovanni, his machine for propelling a wheel by a blast of steam, [45]

Brewster, Dr., [79]

Brunton, Mr., his improved furnace described, [130]

Canals, transport on, [208].
Experiments with boats on, [209],
Comparison of with railroads, [210]

Cartwright, Rev. Mr., description of his improvements in the steam engine, [142]

Cawley, John, [61]

"Century of Inventions" by the Marquis of Worcester, [46]

Chapman, Messrs., obtain a patent for working a locomotive by means of a chain, [162]

Church, Dr., his steam carriage, [239]

Cohesion, attraction of, [32]

Condensation of solids, [28]

Condensation by jet, accidental discovery of, [65]

Cornwall, reports of duty of steam engines in, [303]

Cotton, processes in the culture of, [18]

Cylinder, its proportions, [300]

D valve, description of the, [113]

Damper, the, [126]

Duty of a steam engine, [291]

Duty, reports of, in Cornwall, [303]

Eccentric; description of the, [111]

Edelcrantz, the Chevalier, [127]

Farey, Mr., his statement respecting the variations in the work of different steam engines, [133]

Fluids, property of, [21]

Fly-wheel, introduction of the, [104]

Four-way cock, description of the, [115]

Fuel, table of the consumption of, in different locomotives, [180]

Governor, description of the, [105]

Guericke, Otto, inventor of the air-pump, [70]

Gurney, Mr., his steam carriage, [216]

Hackworth, Mr., description of his engine, the "Sanspareil," [173]

Hall, Mr. Samuel, his patent steam engine, [248].
Its advantages for navigation, [249].
Its successful application, [250]

Hamilton, Duke of, [88]

Hancock, Mr. Walter, his steam carriage, [235]

Heat, phenomena of, [29]

Hero of Alexandria, description of his machine, [41]

Hopper, the, or apparatus for supplying the fire-place with coals, [131]

Hornblower, Mr., his double-cylinder engine, [134]

Horse power and steam power, comparison between, [202]

Horse power of an engine, [291].
Method of calculating it, [293]

Howard, Mr. Thomas, his patent steam engine, [253].
Its advantages in navigation, [256]

Huskisson, Mr., [154]

Inclined planes, their injurious effects on railroads, [194].
Methods proposed to remedy these, [194]

India, steam communication with, [271]

Kendal and Preston canal, speed of boats on, [209]

Leeds and Selby railroad, [317]

Leicester and Swannington railroad, [317]

Leupold, his "Theatrum Machinarum," [116].
His engine described, [147]

Liquids converted into vapour by the application of heat, [27].
Difference of temperatures of, [35]

Liverpool and Manchester railroad, effects of the introduction of steam transport on, [152].
Want of experience in the construction of the engines, [154].
Proceedings of the directors, [167].
Premium offered by them for the best engine, [169].
Experiments made on, [183].
Passengers the chief source of profit to the proprietors, [204]

Liverpool and London, supposed advantages from the connexion of these places by railroad, [206]

Llangennech coal, its economy, [267]

Locomotive engines, description of the "Rocket," [171].
The "Sanspareil," [173].
The "Novelty," [175].
Mr. Booth's method of using tubes to conduct heated air through boilers, [177].
Mr. Stephenson's method of subdividing the flue, [179].
Amount of fuel consumed in, [180].
Progressive improvement of, [180].
Description of an improved form of engine, [181].
Circumstances on which their efficiency depends, [183].
Experiments with, on Liverpool and Manchester railroad, [184].
Defects of, [186].
Improvement in the method of tubing, [188].
Proposed methods for working them on levels and inclined planes, [194].
Extraordinary speed and power of, [204].
Their introduction on turnpike roads, [213]

Locomotive power, expense of, [188]

Locomotive boilers, improved form of, [177]

Machines, definition of, [19]

Manufactures, motions required in, [19]

Morgan, Mr., his patent paddle-wheel, [259]

Morland, Sir Samuel, his application of steam to raise water, [47]

Motion, a primary agent in the cultivation of cotton, [18].
Variety of, [19]

Murray, Mr., description of his suggested slide valve, [113]

Newcomen, Thomas, and John Cawley, turn their attention to the practicability of applying steam engines to the drainage of mines, [61]

Newcomen, Thomas, his construction of the atmospheric engine, [63]

"Novelty," description of the, [175]

Ogle, Mr., his steam carriage, [239]

Oldham, Mr., his modification of the self-regulating furnace, [132]

Paddle-wheel, the common one, [257].
Mr. Morgan's patent one, [259]

Papin, Denis, his contrivance, by which atmospheric pressure is rendered available as a mechanical agent, [48].
Description of his steam engine, [71]

Parallel motion, description of the, [95]

Piston, its velocity, [302]

Post-office steam packets, their speed, [268]

Potter, Humphrey, his contrivance for working the valves, [67]

Power of a steam engine, how estimated, [291]

Railroads, first introduction of locomotives on, [151].
Important effects to be expected from their adoption, [155].
Imaginary difficulty respecting the progression of carriages on, [160].
Various methods resorted to, to remedy this supposed difficulty, [161].
One of these methods described, [162].
Comparative estimate of the expenses of locomotive and stationary engines, [168].
Difficulties arising from changes of level, [192].
Their great extension, [206].
Comparison of, with turnpike roads, [213].
Inclined planes on, [194]

Railway speculators, plain rules for, [307]

Roads, their resistance to draft, [213].
Compared with railroads, [213]

Robinson, Dr., [73]

Roebuck, Dr., assistance rendered by him to Watt, [87].
His embarrassments, [88]

"Rocket," description of the, [171]

Savery, Thomas, obtains a patent for an engine to raise water, [49].
His discovery of the principle of condensation, [49].
Constructs the first engine brought into operation, [50].
Description of, [51].
Inefficiency of, [57].
Great consumption of fuel necessary in his engines, [60].
Different purposes to which he proposed to apply the steam engine, [61].
Limited power of his engine, [69]

"Sanspareil", description of the, [173]

Smeaton turns his attention to the details of the atmospheric engines, [73]

Solids converted into liquids by the application of heat, [27]

Solomon De Caus, description of the apparatus of, [43]

Somerset, Edward, Marquis of Worcester, invention of the steam engine ascribed to him, [45].
Description of his contrivance, [45].
Similar to Savery's, [46].
His "Century of Inventions," [46]

Steam carriages, Mr. Gurney's, [216].
Mr. Hancock's, [235].
Mr. Ogle's, [238].
Dr. Church's, [239]

Steam, its properties described, [30].
Its mechanical power in proportion to the water evaporated, [277].
Its volume, [279].
Its quantity of heat, [279].
Its power in respect of fuel, [280].
Its expansive action, how advantageous, [280].
Combination of expansion with condensation, [285].
High-pressure, its expansive action, [288].
Examples illustrative of its mechanical force, [305]

Steam engine, first mover in, [19].
Physical effects connected with, [20].
Claims to the invention of, [38].
Efficacy of, as a mechanical agent, [39].
First brought into operation by Savery, [50].
Its inefficiency, [58].
First proposed to be applied to the drainage of mines, [61].
Accidental discovery of condensation by jet, [65].
Further improvements by Humphrey Potter and Beighton, [67],
[68].
Description of Papin's engine, [71].
First experiments of Watt and subsequent improvements, [73].
Dr. Black's theory of latent heat, [76].
Watt's method of condensation, [76].
Further improvements of Watt, [77].
Description of Watt's single-acting engine, [80].
The cold water pump, [86].
The hot water pump, [86].
Erection of a specimen engine at Soho, and gradual demand for them, [89].
The single-acting engine inapplicable to manufactures, [91].
The double-acting engine, [92].
Invention of the parallel motion, [95].
Introduction of the rotatory motion, [100].
The fly-wheel, [104].
The governor, [105].
The throttle valve, [105].
The eccentric, [111].
The D valve, [113].
The four-way cock, [115].
Methods for ascertaining the level of water in the boiler, [118].
The engine made to feed its own boiler, [120].
Waste of water prevented, [121].
The steam gauge, [122].
Barometer gauge, [123].
The damper, [125].
Methods proposed for preventing the waste of fuel, [128].
Mr. Brunton's furnace described, [130].
Mr. Oldham's modification of the self-regulating furnace, [132].
Improvements by Hornblower and Woolf, [134].
Description of the improvements of Mr. Cartwright, [142].
High-pressure engines, [145].
Leupold's engine described, [147].
Construction of the first high-pressure engine by Messrs. Trevithick and Vivian, [148].
First application of the steam engine to propel carriages on railroads, [151].
How applied to navigation, [242].
Marine engine; its form and arrangement, [243].
Mr. Howard's patent engine described, [253].
Mr. Hall's engine described, [248]

Steam gauge, the, [122]

Steam navigation, incredulity which existed respecting, [159].
The limit of its present powers, [264]

Steam vessels, their average speed, [265].
Their average consumption of fuel, [265].
Proportion of their power to their tonnage, [266].
Speed of post-office packets, [268].
Iron steam vessels, [269].
American vessel called the "Cigar Boat," its great speed, [270]

Stephenson's, Mr., description of an engine constructed by him, [164].
Premium awarded to this engine by the Liverpool and Manchester Railway Directors, [170].
His method of dividing the flues, [179]

Stephenson and Lock, Messrs., appointed by the Directors of the Liverpool and Manchester Railroad to make reports on the merits of various railroads, [167]

Sun and planet wheels, [101]

Thermometer, description of, [24]

Throttle valve, use of, [104]

Traction, force of, on a railroad, [192]

Tredgold, [70]

Trevithick and Vivian, Messrs., construct the first high-pressure engine used in this country, [148]

United States, steam communication with, [274]

Vacuum, production of, by experiment, [37]

Vapour, elastic, force of, [35]

Valves, Watt's method of working the, [109]

Walker and Rastrick, Messrs., apparent discrepancy of their estimated expense of locomotive power, [189]

Washborough takes out a patent for Watt's invention of the rotatory motion, [100]

Water, sea, injurious to marine boilers, [245].
How remedied by blowing out, [246]

Watt, James, important discoveries of, [39].
His acquaintance with Dr. Robinson and first experiments on the steam engine, [73].
His subsequent improvements, [75].
His method of condensation, [76].
His first introduction of the air-pump into the steam engine, [77].
Further improvements, [78].
His difficulties, [78].
Description of his single-acting engine, [80].
His introduction to Dr. Roebuck, [88].
Erects his first engine on the estate of the Duke of Hamilton, [88].
After further improvements, obtains a patent for this engine, in conjunction with Roebuck, [88].
His difficulties owing to Dr. Roebuck's failure, and subsequent connexion with Bolton, [88].
Obtains an extension of his patent, [89].
Ingenious invention of, to determine the rate of remuneration he should receive, [89].
His invention of the parallel motion, [95].
His method for producing a rotatory motion anticipated by Washborough, who takes out a patent for it, [101].
His contrivance of the governor, [104].
His method of working the valves, [109].
His suggestion of the D valve, [113]

Wood, Mr. Nicholas, [168]

Woolf, Mr., his improvements in the steam engine, [134].
Obtains a patent for the double-cylinder engine, [137]

JUST PUBLISHED, IN ONE VOLUME, 8VO.

MATHEMATICS FOR PRACTICAL MEN;
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BY OLINTHUS GREGORY, LL. D., F. R. A. S.

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SECOND EDITION, CORRECTED AND IMPROVED.

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"This treatise is intended and admirably calculated to supply the deficiency in the means of mathematical instruction to those who have neither time nor inclination to peruse numerous abstract treatises in the same departments. It has, besides the claims of a good elementary manual, the merit of embracing several of the most interesting and important departments of Mechanics, applying to these the rules and principles embraced in the earlier sections of the work.

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Letter from Albert B. Dod, Professor of Mathematics in the College of New Jersey.

"Messrs. Carey & Hart,

"Gentlemen,—I am glad to learn that you have published an American edition of Dr. Gregory's 'Mathematics for Practical Men.' I have for some time been acquainted with this work, and I esteem it highly. It contains the best digest, within my knowledge, of such scientific facts and principles, involved in the subjects of which it treats, as are susceptible of direct practical application. While it avoids such details of investigation and processes of mathematical reasoning as would render it unintelligible to the general reader, it equally avoids the sacrifice of precision in its statement of scientific results, which is too often made in popular treatises upon the Mathematics and Natural Philosophy. The author has succeeded to a remarkable degree in collecting such truths as will be found generally useful, and in presenting them, in an available form, to the practical mechanic. To such, the work cannot be too strongly recommended; and to the student, too, it will often be found highly useful as a book of reference.

"With much respect,

"Your obedient servant,

"ALBERT B. DOD,
"Professor of Mathematics in the College of New Jersey.

"Princeton, Nov. 11, 1834."

Extract of a Letter from Edward H. Courtenay, Professor of Mathematics in the University of Pennsylvania.

"The design of the author—that of furnishing a valuable collection of rules and theorems for the use of such as are unable, from the want of time and previous preparation, to investigate mathematical principles—appears to have been very successfully attained in the present volume. The information which it affords in various branches of the pure and mixed Mathematics embraces a great variety of subjects, is arranged conveniently, and is in general conveyed in accurate and concise terms. To THE ENGINEER, THE ARCHITECT, THE MECHANIC—indeed to all for whom results are chiefly necessary—the work will doubtless form a very valuable acquisition."

Letter from Charles Davies, Professor of Mathematics in the Military Academy, West Point.

"Military Academy, West Point, May 14th, 1835.

"To Messrs. E. L. Carey & A. Hart,—

"The 'Mathematics for Practical Men,' by Dr. Gregory, which you have recently published, is a work that cannot fail to be extensively useful.

"It embraces, within a comparatively small compass, all the rules and formulas for mathematical computation, and all the practical results of mechanical philosophy. It is, indeed, a collection of the useful results of science and the interesting facts which have been developed by experience. It may safely be said, that no work, of the same extent, contains so much information, with the rules for applying it to practical purposes.

"I have the honour to be,

"With great respect,
"Your obedient servant,

"CHARLES DAVIES,
"Professor of Mathematics."

Extract from a Letter from J. A. Miller, Professor of Mathematics in Mount St. Mary's College, Emmettsburg, Md.

"Since the London edition of Gregory's Mathematics for Practical Men appeared in this country, it has been much used in this institution. The accuracy of its definitions, its beautiful systematic arrangement, the many simplified and facilitated methods which it proposes, and its highly practical character, must recommend it strongly to public patronage, as one of the very best works which have lately issued from the press. I have examined your edition of this valuable work sufficiently to say with confidence that it is very accurately printed."