valetudinarian with impaired digestive organs. He was a victim of indigestion, diarrhoea, and, later on, of insomnia. He has had to submit to the most rigid observance of diet and regimen. All this, however, was only half of Rky's life. To him the aolitical side was eauallv imoortant. As a bov he had been attracted to the ~ra'hmoSaraj movement which aimed at thc abolition of the caste system, the removal of social inequalities (including the social relations between Englishmen and Indians), and the uplifting of women by the spread of education among them. While a student in Edinburgh Rky wrote: "We find there is a tendency among a certain class of writers to single out some of the worst types of Mohammedan despots and bigots, and institute a comparison between the India under them and the India of today. This is very fair, no doubt; but will the Mohammedan rule su5er by comparison with ours? I t is forgotten that a t the time when a Queen of England was flinging into flames and hurling into dungeons those of her own subjects who had the misfortune to differ from her on dogmatic niceties, the great Mogul Akbar had proclaimed the principles of universal toleration, had invited the moulvie, the pandit, the rabbi, and the missionary to his court, and had held philosophical disquisitions with them on the merits of their various religions." Ray was responsible for Gandhi's first appearance on a Calcutta platform. This was in 1902 and even a t that time "the ideas of Satyagrapha and Passive Resistance which were destined to be such potent factors after a generation had already germinated." It seems to be quite certain that the English in India have been unwise in the extent to which they blocked the rise of Indians in the Civil Setvice. On the other hand R i y does not draw a flattering picture of the Bengali. Part of the general misunderstandine is that R i v fwuses on the soecial Beneali - and the ~u~l~h~~ovem on mthe e naverage t ~ingali. C o a ~ e ~Ur N . IYBRS~Y W I L ~ E D. R BANCXOFI
.~~~~~~~~~. ~~~
.
IraAcn, Nsw Yoax
Huomnas OF BORON A N D SILICON.A l f f ~ d Slack, Professor of Inorganic Chemistry, Technirche Hochschule, Karlsruhc. Comcll Univcrsitv Press. Ithaen. New York. 1933. vt T 250 pp. 28 Figs.. 8 plates. 15.5 ~ 2 cm. 3 $2.00
It demonstrates the author's clear and broad concepts of the problems confronting science. It is followed by a single chapter on the investigations of the hydrides of silicon. These hydrides are prepared by the action of hydrochloric acid solution of magnesium silicide, MgzSi, which gives rise to the formation of the well-defined comnounds.. Si&... Si,H.. and.a t least . . . %Ha. . ~ SiHlo. .~ two other higher hydrides. The halogen substitution products present another interesting series of compounds, while the oxygen and nitrogen derivatives are unique in their chemical and physical properties. Due to the pronounced affinity of silicon for oxygen, the chemistry of these hydrides is by no means as extensive as that of the analogous compounds of carbon. Carbon stands alone in its ability to form a large number of different types of stable combinations with other elements. Attempts are made to explain the formation of these hydrides by the reaction mentioned above, but it appears that there is not at present any mechanism entirely free from criticism. The greater part of the bwk is confined to the studies of the hydrides of boron. These compounds are prepared in a manner analogous to the preparation of the silicon hydrides, that is, through the action of hydrochloric acid on magnesium boride. Several hydrides have been established here, namely, B*Hs. B,H,u, B6Ha, B5H,,, BsHlo, and B , d h . An extensive account is given of their chemical and physical properties. It is also interesting to learn that BH8 has never been prepared and probably does not exist. Thus a study of the chemistry of these hydrides may lead to some very interesting results relative to our concepts of valence. The hydrides mentioned above do not appear to behave in accordance with the expectations of the normal valence relations. Accordingly, much of the work in this field has been directed toward a solution of these valence problems. Some studies have been made with the alkyl derivatives of boron to aid this problem. One is a t once impressed by the unique methods employed to prepare and study the hydrogen compounds of boron and silicon. Here Stock has contributed outstanding and invaluable twls for the worker who is required to study the properties of substances in the absence of air and moisture. Much of this technic is already in use in many of our academic and technical laboratories: and without it. manv research orablems would be areatly handicapped today. Mention may be given here to only a few manipulations, such as the mercury float-valve, special containers for storing gases, vessels for the determination of the vapor density of a substance in the absence of lubricants, the floating balance for density and pressure measurements, shaking devices, the determination of the melting point of a substance in oacuo a t low temperatures, low-temperature fractional distillation and thermometer, and condensation. the use of the vaoor-rrressure . . many methods for c ~ n y i n gout reactions i n varuo at low temperatures. These manipulations arc thoroughly described and illustrated in the Appendix of the t e x t . Complete references to the literature are also given. This book should be in every library and in the hands of workers interested not only in the hydrides of these metals, but in the physical and chemical properties of substances which caunot be studied under the usual laboratory conditions. ~
Professor Stock, the George Fisher Baker Non-resident Lecturer in Chemistry at Camell University in 1932, presented a series of lectures describing the results of his investigations, extending over a period of mare than twenty years, on the preparation, the chemical and physical properties, and the structure of the hydrides of boron and silicon. It is indeed gratifying to see these lectures collected as a unit which maintains the excellent standards established by the previous lecturers of this series. The value of the text is augmented through the careful revision by Professor J. Papish and Dr. W. J. O'Leary of the preliminary translation made by Cleveland Abbe, Jr. The aims and accomplishments of the author are admirably expressed in the followinglines which are quoted from his chapter entitled Retrospect: "In nature boron's dominating affinity for oxygen restricts it to the monotonous rile of boric acid and the borates, and prevents it from competing with carbon, its neighbor in the periodic system. "It is very stimulating to observe the change from the rich chemical possibilities of carbon, the fountain of terrestrial life, as one passes to its three neighboring elements boron, silicon, and "it-"=-..
..
"To be sure, the three refractory non-metals carbon, boron. and silicon are so strikingly similar in their elemental form that even the older chemistry included them in a limited p u p . Their chemical behavior. however. showed hardly any recognizable similarities. Carbon had the greatest mobility and diversity. while silicon and boron were unvarying and restricted in their reactions. But today it is known that in the latter two elements there also slumber rich chemical possibilities which are not available in nature because of the great a5nity of silicon and boron for oxygen-possibilities which can be wakened only by the resources of the laboratory." An introductory lecture is given in the series on The Present Status of the Natural S e n c e s which is exceedingly interesting,
B.n & BAUER,INC.,3W Pearl Street. New York City, announces the publication of a new 28-page bwklet, No. U 3 , on the "Zsigmondy Ultrafiltration Apparatus and Membranes." These membranes, which are made from cellulose esters, h a w been used extensively in all branches of science for work in ultrafiltration, electroultrafiltration. dialysis, electrodialysis, osmosis, and other work requiring semipermeable membranes of graduated porosity. The booklet contains a s u m y of work that has been done in the field as well as a bibliography of 124 literature references. A second publication is a 14-page listing entitled "Gruebler-Hallborn Stains and Preparationsfor Miffoscopy." Copies of this catalog and list will be sent on request.
