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THE

STEAM-ENGINE,

ITS HISTORY AND MECHANISM:

BEING

Descriptions and Ellustrations

OF THE

STATIONARY, LOCOMOTIVE, AND MARINE ENGINE.

For the Use of Schools and Students.

BY ROBERT SCOTT BURN,

EDITOR OF THE "ILLUSTRATED LONDON DRAWING-BOOK;" "MECHANICS AND MECHANISM ;” "ARCHITECTURAL, ENGINEERING, AND MECHANICAL DRAWING-BOOK;" "ILLUSTRATED PRACTICAL GEOMETRY," ETC.

LONDON:

H. INGRAM AND CO.,

MILFORD HOUSE, MILFORD LANE, STRAND;

AND

W. S. ORR AND CO., AMEN CORNER, PATERNOSTER ROW.

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CONTENTS.

THE HISTORY OF THE INTRODUCTION OF THE MODERN STEAM-ENGINE.

James Watt, historical notice of, 30. Watt's experiments on steam, 31. Watt's first

patent for steam-engines, 35. Watt's arrangement with Roebuck for working the

patent, 35. Watt's arrangement with Bolton, of Soho, 36. Watt's arrangement of

cylinder valves for pumping engines, 39. Watt's mechanism for working the valves,

40. Watt's improved cylinder, 41. Watt's expansive steam-engine, 41. Watt's "In-

dicator," for ascertaining the power of engine, 44. Watt's single-acting engine, 45.

Watt, application of the crank to the engine of, 47. Watt's "sun-and-planet wheels,"

49. Watt, attachment of the beam to the piston-rod in the first engine of, 50. Watt's

parallel motion, 50. Watt's throttle-valve, 50. Watt's governor, 50.
Watt's

spindle or tappet valves for cylinder, 51. Double-acting engine of Watt, 52. Watt's

wagon boilers with fittings, 53. Arago's éloge on the character and genius of James

Watt, 55, Double cylinder engine, Hornblower's, 59. Cartwright's steam-engine, 61.

Leopold's high-pressure engine, 64. Trevethick and Vivian's high-pressure engine,

65. Pumping engine for mines, modern, 66. Double cylinder engine, M'Naught's, 67.

Double cylinder engine for factories, on the marine principle, 68-70. Double cylinder

engine, Varley's, 70. High-pressure steam-engine, 71. Beam engine, high-pressure,

71. Crank-overhead high-pressure steam-engine, 72. Fairbairn's crank-overhead

high-pressure steam-engine, 73. Crosskill's crank-overhead high-pressure steam-

engine, 74. Table high-pressure engine, 75. Horizontal steam-engine, high-pressure,

76. Oscillating engine, high-pressure, by Watt, 77. Oscillating engine, high-pres-

sure, by Evans, 78. Oscillating engine, high-pressure, by Pope, 79. Pendulous

engine, by Joyce, 80. Portable agricultural engine, by Clayton and Shuttleworth, 81.

Portable agricultural engine, by Barrett and Exhall, 82. Gough's portable agricultural

engine for railway excavation, 82. Portable agricultural engine, by Gough, 83.

Gough's portable agricultural steam-pump, 84. Portable agricultural steam-plough,

INTRODUCTORY CHAPTER.

THE PROPERTIES OF STEAM.

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EFORE entering upon the consideration of the historical and mechanical details of the steam-engine, it will be necessary to explain as briefly as possible the nature and properties of steam. It is but just, however, to state, that the new theory of heat, now being submitted to the test of experiment, will modify very much the theory of the steam-engine. Until the new views, however, have been conclusively affirmed, it would be premature here to specify them; we shall therefore confine ourselves to a statement of the theory of the steam-engine as generally received.

When a quantity of water is heated until it arrives at a certain fixed temperature, an elastic fluid or aqueous vapour is evolved; this is called steam, and resembles in many of its properties common air. Like air, it is elastic, capable of being reduced in bulk by compression; the pressure which it exerts in the vessel into which it is compressed being exactly in proportion to the amount of compression. (See volume on Natural Philosophy in this series.) Like air, steam is also capable of an increase of volume or bulk; this expansion reducing the pressure on the vessel in which it is allowed to expand just in proportion to the amount of expansion. The first property of steam now mentioned is termed its elasticity, the second its expansibility; although, having these properties in common with fluid gases, steam is distinguished by the term of aqueous vapour, inasmuch as it differs from a gas, which retains permanently its gaseous condition under ordinary circumstances; while steam requires to be kept

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