CONTENTS,

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THEORY OF THE PRODUCTION OF GAS-LIGHT;AND DESCRIPTION OF A PORTABLE APPA-RATUS FOR ILLUSTRATING, IN THE SMALLWAY, THE GENERAL NATURE OF THE NEWSYSTEM OF PROCURING LIGHT. Page 77.

Philosophy of the production of coal-gas.—Characters of the vari-. ous products which the gas-light process affords, their quantities,and modes of obtaining them.—Quantity of gas obtainable froma given weight of coal.—Illuminating power of a given bulk ofcoal-gas compared with the illuminating power of a given weightof tallow' candles.—Practical directions with regard to the pro-duction of the gas from coal.—Its chemical constitution and ana-lysis. Pitcoal is not the only substance which affords carburettedhidrogen gas.—This gas exists ready formed in nature.—Mode ofcollecting it when found native.—Is given.out by all kinds ofvegetable matter, submitted to distillation in close vessels.—Othersources of obtaining this gazeous fluid.—Practical directionswith regard to the method of, obtaining from coal, this gazeoussubstance, as best suited for illumination.—Chemical constitutionof coal-gas,—How ascertained.

UTILITY OF THE GAS-LIGHT ILLUMINATIONWITH REGARD TO PUBLIC AND PRIVATEECONOMY. 99.

Objects to which the new system of lighting with gas may be bene-ficially applied.—Capital advantages of the gas-light illumination.—Places and public edifices lighted with coal-gas in this metro-polis.—Situations best suited for the application of gas-lights.—places where it cannot be used to advantage.—Illumination ofbarracks, arsenals, dock yards, &c. with coal-gas.—Further ob-servations on this subject.—Great heat produced by gas-lights.—Reason why the flame of coal-gas produces more heat than theflame of candles and lamps.—Admeasurement of the compara-tive degrees of heat produced by gas-lights, oil lamps, tallowand wax candles, &c.—Gas lamps and burners, various kindsof.—Ornamental chandeliers and candelabras, for applying coal-gas as a substitute for oil.—Other products obtainable from coalbesides gas.— Coke. —Its nature.—Combustion of it.—Producesa more strong and lasting heat than coal.—Explanation of thisfact.—Advantages resulting from the use of coke as fuel.—Disad-vantages of its application in certain circumstances.—Relativeeffect of heat produced by equal quantities of coke and charcoal.•—Method of measuring the comparative effect of different kindsof fuel in producing heat.—Capital advantages resulting fromthe application of coke, as fuel, in the art of burning lime.—-plaster of Paris, bricks, &c.—Quantity of coke obtainable froms. certain quantity of pit-coal.—Kind of coke best ouited for