SCIENCE a EO a 
butter, if not of the best quality, will have a still greater competitor in mar- 
garine than it has had in the past. The book should find readers in all persons 
having any connexion with such foods, as weli as in the technical workers in fats 
and oils. 
COMMERCIAL OILS, VEGETABLE AND ANIMAL, J. F. Laucks, B.S., 
M.S., pp. viii + 138. John Wiley & Sons, New York, 1919. ‘This 
book is. intended primarily for the man in the oil trade, consequently 
much of the information refers to trade rules, specifications, and maxi- 
mum and minimum values of the so-called constants to show what 
ean reasonably be expected in commercial practice. As many Oriental 
oils are being imported into the Pacifie coast ports of the United States of 
America, their characteristics are given separately, as they so often vary from 
the general standard of oils from “other parts. In some cases, this is due to 
clintatic and soil conditions, and in others to the treatment, to carelessness, or to 
unavoidable commercial conditions. ‘These differences have often led to buyers 
rejecting Oriental oils. We haye had a similar case recently of sandalwood oil 
from West Australia. This cannot be made to conform to the B.P. standard 
for Santalum album oil. Laucks recommends that new standards should be 
drawn for these Eastern and similar oils. 
The book contains but four chapters. Chapter I. (pp. 1-29) gives a very useful 
and handy account of the general properties (physical- -chemical), classification, 
preparation from raw material, and examination. All useless tests are discarded, 
and the special value of any particular test retained is clearly indicated, e.9., 
Saponification No., the Iodine No., and the Refractive Index. Not much reliance 
is placed on Reichert-Meissl No. and the Acetyl Value, owing to these values 
increasing with the age of the oil. In examining castor oil, howev er, the acetyl 
value is especially important; and similarly ‘the Reichert-Meissl No. is of. 
importance in butter-fat, and coconut, porpoise, croton, and maize oils. A 
Specimen examination (pp. 26-29) clearly indicates the ‘general method. 
Chapter IT. (pp. 30-105) gives the detailed information on the individual oils 
which follow the classification of Lewkowitsch, and hence includes solid and 
liquid waxes. 
The remaining two chapters deal with the uses of oils, and sampling. There 
are given the oils used in making margarine, varnishes and paints, lubricants, 
soaps and candles, polishes, and the various substitutes, e.g., rubber and butter. 
A tabulated account is given as an appendix of many less common oils. 
The hydrogenation of oils is dismissed in less than a page. ‘This is a pity, 
when we consider what great changes have been brought about in the commercial 
handling of oils that have been hardened. 
The hook is well printed, and forms a well-condensed and convenient reference 
book. 
CATALYTIC HYDROGENATION AND REDUCTION, Edward B. Maxted, 
Ph.D., B.Se., F.C.S., pp. viii -+ 104, with 12 illustrations. London, 1919. J. & A. 
Churchill. 4s. 6d. This is a small book of the series of Text Books of Chemical 
Research and Engineering, edited by W. P. Dreaper, F.1.C. It is writen with the 
object of presenting, in an easily accessible form, the numerous examples of cata- 
lytic hydrogenation which have hee n published from time to time in much scattered 
literature. Special attention is given to experimental methods. The first three 
chapters (pp. 1-27) are introductory, and deal with the preparation of catalysts, 
e.g., the Nickel group (Ni, Fe, Co. and Cu), and the Platinum group and colloidal 
condition, and the principal methods of catalytic hydrogenation. The next two 
- chapters cover the hydrogenation of unsaturated chains and rings; the sixth 
chapter on miscellaneous reductions: and the seventh on the reverse reaction of 
dehydrogenation, chiefly by copper and palladium. References to all the original 
papers are given, and though a small book, the matter is printed in large, clear 
type, and the numerous organic formule are very well done. 
The closing chapter _( 82. 101) gives an account of the technical hydrogenation 
of unsaturated oils, the preparation and efficient plant for production of a “catalyst 
on a large scale, the commercial preparation of pure hydrogen, and the deter-: 
mination of the Iodine value, Refractive Index, and the detection of Ni. Diagrams 
are given for plant for converting oils into solid forms, and details of tempera- 
tures, pressures, and periods, &c., are given. A name and a subject index are 
added. Though small, the book is packed with details of sound, practical 
information, Which is quite up to date. 
64 
