A VERY elementary account of the subject suitable for students in technical schools and classes will be found in this book. The chemistry of the materials and processes are not dealt with, formulae and equations being purposely omitted. There is no index. On p. 128 the composition of “modern coal gas” is given as containing only 8 per cent, of carbon monoxide and 3-5 of “oxygen, nitrogen, etc.” This must refer to genuine coal gas and not to the “modern ” variety. No mention of fat hardening is made.
Oils, Fats, and Fuels.
By. Pp. viii + 143. (London: Blackie and Son, Ltd., 1921.) 3s. 6d. net.