Advertisement to the Second Edition.

THIS Edition has been carefully revised throughout, and many new Illustrations and Examples added, which it is hoped will increase its usefulness to Students at the Universities and in Schools.

In accordance with suggestions from many engaged in tuition, Answers to all the Examples have been given at the end of the book.

The Author wishes to acknowledge the assistance given him by his brother, the Rev. S. G. Phear, Fellow of Emmanuel College, in reading the proof sheets, adding many Examples, and furnishing the Solutions and Answers.

Dec. 1st, 1857.

CONTENTS.

SECTION I.

PRELIMINARY DEFINITIONS AND EXPLANATIONS.

Definition of a fluid, 1; explanation of the term fluid pressure and the definition of its measure, 2, 3, 4; a supposed solidification of a portion of fluid does not affect its action upon the remainder, 5; hydrostatic action of rigid surfaces upon fluids, 6; transmission of pressure by a fluid, 7; distinction between elastic and inelastic fluids, 8; measures of mass, density, and specific gravity, 9, 10, 11, 12.

Examples

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II

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SECTION II.

INELASTIC FLUIDS.

Definition of vertical and horizontal; pressure at a point in a heavy fluid, 13; pressure uniform in the same horizontal plane, 14; free surface horizontal, 15; common surface of two fluids which do not mix, 16; heights of the free surfaces above this, 17; total normal pressure on a surface immersed, 18; resultant of the same pressure, 19; conditions which a floating body satisfies, 20; stable, unstable and neutral equilibrium, 21; conditions of a body's sinking, rising, or remaining stationary when immersed totally in a fluid, 22, 23, 24, 25; Hydrostatic Balance, 26; methods for finding the specific gravity of a body or fluid, 27, 28, 29, 30; Common Hydrometer, 31; Nicholson's Hydrometer, 32; specific gravity of a mixed fluid, 33.

Examples, 31

12

43

SECTION III.
ELASTIC FLUIDS.

Pressure in elastic fluids sometimes termed elastic force, 34; assumed to be uniform under certain conditions, 35; Barometer, 36; Boyle's Law, 37; pressure varies as the density, 38; to find k for air, 38*; law of density in the atmosphere, 39; barometer employed to measure heights, 40; Air-Pump, 41; density after the nth stroke, 42; causes limiting the exhaustion, 43; Hawksbee's air-pump, 44; Smeaton's ditto, 45; the Condenser, 46; Common Pump, 47; tension of its piston-rod, 48; Lifting Pump, 49; Forcing Pump, 50; Bramah's Press, 51; Siphon, 52, 53; Diving-Bell, 54; Atmospheric Steam Engine, 55; Watt's improvements, 56; Double-Action Steam Engine, 57.

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85

SECTION IV.

GENERAL PROPOSITIONS.

Virtual Velocities, 58; resolved parts of normal pressures upon the surface of a vessel containing heavy fluid, 59, 60, 61, 62; ditto, when the included fluid is elastic, 63; Center of Pressure, 64; Barker's Mill, 65; free surface of a revolving fluid under certain conditions, 66; resultant pressure upon the surface of a body immersed in any fluid whatever, 67; tension at any point in a solid how measured, 68; tension at any point of a cylindrical surface containing fluid, 69, 69*; ditto for a spherical surface, (694), (69A*); mode of graduating a barometer, 70, 71, 72; Wheel Barometer, 73.

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Examples, 104

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SECTION V.

MIXTURE OF GASES.-VAPOUR.

Boyle's law holds for a mixture of gases, 74; gas absorbed by a liquid in contact with it, 75; relation between change of temperature and change of volume in all substances, 76; meaning of the term thermometer, 77; mercurial thermometer, 78; filling the thermometer; comparative expansions of substances, 79; temperature measured by the thermometer, 80; expansion of water, 81; proof of the formula p= kp (1 + at), 82; relations between the heat absorbed, the resulting temperature and the mass, for a uniform substance, 83; algebraical expression of the same, 84; ditto for a compound substance, 85; specific heat, 86; algebraical formula, 87; specific heat of gases, 88; all substances made to experience the solid liquid or gaseous state by the application of corresponding amount of heat, 89; vapour, 90; saturation density, and its dewpoint, 91; under what circumstances vapours follow Boyle's law, or not, 92; gases, 93; the preceding results independent of the number of gases present, 94, 95; ebullition of water, 96; algebraical formula connecting the pressures and temperatuure for a mixture of gas and vapour, 97; latent heat, 98; effects produced by absorption of heat in evaporation, 99; contraction produces the opposite results to dilatation, 100; hygrometrical state of the atmosphere; 101; Clouds, 102; Rain, 103; causes producing these effects, 104; Snow and Hail, 105; Dew, Hoar-frost, &c., 107; Conduction, Convection, and Radiation of heat, 108; cause of dew, &c., 109; Dew-point, 110; results of the law of expansion in water, 111.

General Examples.

Answers to the Examples

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