Note 52 — PART XIV.
Reading edition
Mr. Dalton’s method of ascertaining the comparative effect of heat evolved during the combustion of inflammable gases, and other substances capable of burning with flame, (Dalton’s System of Chemistry, vol. I. p. 76,) is simple, easy, and accurate. It is as follows:
Take a bladder of any size, (let us suppose for the sake of illustration, the bladder to hold 30,000 grains of water,) and having furnished it with a stop-cock and small jet pipe, fill it with the combustible gas the heating power of which is to be tried. Take also a tinned iron vessel with a concave bottom of the same capacity, pour into it as much water as will make the vessel and water together equal to the bulk of the water in the bladder, viz. 30,000 grains. Then set fire to the gas at the orifice of the pipe, bring the point of the flame under the bottom of the tinned vessel, and suffer it to burn there, by squeezing the bladder till the whole of the gas is consumed. The increase of temperature of the water in the tinned vessel before and after the experiment, expresses very accurately the heating power of the given bulk of the inflammable gas. It was thus proved that—
Olifiant gas raises an equal volume of water 14 deg.
Carburetted hydrogen, or coal gas 10
Carbonic oxid gas 4
Hydrogen gas 5
Spermaceti oil, 10 grains burnt in a lamp raised 30,000 grains of water 5
Tallow 5
Wax 5,75
Oil of turpentine 3
Spirit of wine 2