276 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS the author has attempted a cursory survey of the remarkable achieve- ments made with electron micro2 scopes. He mentions that a com- prehens. ive review of this field would be obsolete by the time it was printed. However, a mere ten pages devoted to this subject seriously limits the monographs's popular appeal. The book would make smoother reading if the order of chapters and presentation of subjects were changed. For example, Chapters 2 and 3 are written in the intellectual stratosphere. In Chapters 4 and 5 the reader is plunged into sort of a sub-basement and is expected to re- turn to the stratosphere in Chap- ters 6 through 8. Prospective read- ers are advised to first read Chapters 1, 4, 5, 9, 10, 11, and 14. Reserve the other parts of this book for pro- longed study, which will be reward- ing for anyone contemplating use of an electron microscope. A book of this caliber with emphasis on funda- mental principles enables the reader to comprehend the instrument's operation. This is quite remark- able, since no reference is made to the complex electronic circuits re- sponsible for the operation.--W. THOMPSON. WmTv. MINERA•. 0•,. AN• PETRO- •.ATUM, by Erich Meyer, 135 pages, illustrated and indexed, 51/2 X 8a/4 inches. Chemical Publishing Co., Inc., Brooklyn 2, N. ¾. 1950. Price $4.75. About one page on baby oils and another seven pages on cosmetics in general, cover the toilet goods aspect of this little book. The author traces the discovery of white oil, as it is known in the trade, by the Russian Markowni- koff eight years later elaborated by Petroff, through World War I when mineral oil supplies were cut off and production began in the United States. U.S. P. specifications for both solid and liquid petrolatum are re- viewed and discussed. The author possesses a wide knowl- edge of mineral oil and its use in industry. This would enable him to fulfill his desire to close the gap in the literature on mineral oil and petrolatum. However, the author has failed in this reviewer's opinion for the work lacks substance. The litera- ture on mineral oil and petrolatum has hardly been touched on. In fact, the book gives the impression of a hurriedly completed task with the omissions that are always re- flected in the result. Some 25 pages are devoted to the discussion of mineral oil, paraffin wax, and petrolatum in which phys- ical and chemical constants are covered together with a descrip- tion of the methods by which each is obtained. A very sketchy dif- ference between Pennsylvania, Mid- continent Naphthene and mixed base petroleum derivatives is given. This reviewer feels that much more could be told about all four types which would enable one to determine more readily when to choose any par- ticular type for a specific product. The author is aware of this knowl- edge. No doubt these omissions will be repaired in later editions. In general the preparation of the book is good. It is handy in size and easy to read. The data on the testing of mineral oil and petrolatum are indeed useful. You will want this tome in your library in spite of its small size and the fact that it seems a bit over- priced.--M.G.r•N.