THE ANALYST. 97 REVIEW. SELECT METHODS IN FOOD ANALYSIS. By Drs. LEFFMAN and BEAM. (London: Rebman. Price 11s. net.) Since the publication in 1901 of this very useful handbook considerable additions have been made to our knowledge of food chemistry, and many new processes have been devised. This progress, to which American chemists have contributed a very full share, has necessitated a revision of the work and the insertion of much new matter. Among the more important additicns are descriptions of useful distillation and extraction processes; new methods for the detection of natural colours used as substitutes for fruit colours ; improvements in the detection and estimation of form- aldehyde, boric acid, and other preservatives ; and some new information in connec- tion with the analytical chemistry of butter, oleo-margarine, and other fats.The arrangement of the book leaves nothing to be desired, and although the descriptions of analytical processes are invariably brief, in very few cases has compression been secured at the expense of clearness. The estimation of minute traces of arsenic in food products is a matter with which American chemists are perhaps no$ quite so in- timately acquainted as their English colleagues, and the section devoted to this subject is capable of being improved. On p. 62 the operator is told to use 3 grams of zinc in the Marsh-Berzelius flask, and to allow the action to proceed for one hour after the addition of the material to be98 THE ANALYST. tested, It is not quite clear how a sufficient supply of gas is to be obtained by the employment of so small an amount of metal in a test which, according to the authors’ instructions, is to last for rather more than one and a half hours.Nothing, moreover, is said to warn the analyst against the use of (‘ insensitive ” zinc. On p. 91 the size of the pepper-starch granules is curiously said to vary from 0 to 5.5 microns. Mention is made of the use of cocoanut oil as a direct or indirect butter adulterant, but it is to be regretted that the authors do not give more detailed and definite information as to the methods to be employed for its detection. The illustrations are as a rule good, the plate showing the microscopical appearance of certain of the starches being one of the least satisfactory. To the English eye such words as sirwp and analogs have a strange appearance, but the spelling may perhaps be defended on the ground of simplicity, and at least does no violence to the principles of etymo- logical science, The same cannot, however, be said for the word Zevulose. The work is described in the authors’ preface as being intended “for the practical worker in the detection of food adulteration,” and all such will welcome it as one of the best contributions to this important subject which has yet appeared. A. C. C.