The procedure for a combustion is as follows: - FIG.
The observed heat of combustion of sugar is, however, 1354000, so that the error of the rule is here 20 per cent.
A much better approximation to the heat of combustion of such substances is obtained by deducting the oxygen together with the amount of carbon necessary to form C02, and then ascertaining the amount of heat produced by the residual carbon and hydrogen.
Charcoal, coke or anthracite coal are the fuels generally used in slow combustion heating stoves.
The maximum rate of combustion may be as much as so lb of coal per square foot of grate per hour, and in exceptional cases even a greater rate than this has been maintained.