VOL.2, No. 12
RBCBN
The Foundations of Colloid Chemistry. A Selection of Early Papers Bearing on the Subject. Edited, on behalf of the Colloids Committee of the British Aesoeiation, b~ E x a HATSCIEI, F. Inst. P., Lecturer on Colloids at the Sir John Cass Technical Institute. Landon. First edition, Val. I. The MaeMillan Company, New York, 1925. xii 161 pp, 23 X 14.5 em. 56.00.
kind of capillary condensation which proceeds atthe~"rfaceofheterogeneo".liq"idsincontaet." Thus early (183840) was the physical theory of adsorption outlined. Selmi's papers, in addition to the wealth of sharpsighted special obrervationr on "pseudo-~olutions." will interest students alike of chemistry and the history of ideas for the" premonition of the division of colloids into swpensoids and emmisoids and for his searching sketch of the continuity of dispersion af matter The present book represents the latest, but it from true solutions to coarse emulsions and susmay be hoped not the last, activity of t h e British pensions. In this connection he says, "there is. Assaeiation Committee on Colloid Chemistry, however, a special type of associstion of soivte whieh har already sponsored five valuable reports and solvent whieh stands midway between soluon the subject. I t being decided to reprint some tion and emul$ion, because the body dwellinp in of the early literature on eolloidr, the *cope war the vehicle by its complete transparency would narrowed by eliminating papers by living auinduce one t o believe that it 1s dissolved, whereas thors. This bag enabled certain relatively inon the contrary i t is dispersed therein, in Baker, accessible literature on colloid. t o be republished vesicles, or other shapes." (F. 41) He gaep on and belated but desirable attention to be direeted t o note that thi. ir connected with the hydration to the work of certain early pioneers. of the particles, and that with time this hydration The value of such editions as the present cannot relaxes, "with the appearance of iosoluble p r e ~ be easily overrated. Many Ifudents are either cipitate or of g e l a t i n a n effeet whieh shows ibeli unable to refer t o original texts of pioneers' more rapidly on addition of soluble salt in certain work or are not sufficiently attracted thercto. quantities, or other reagents." Selmi'~obrervaYet the contact with such fundamental p a p a tions on the smaliners of the temperature and should not be mi..ed. The pioneers did not devolume changes in colloid reactions, such as scribe their obreruatian. in a terminology alcoagvlation and dispersion, afford another notable ready shopworn and oaer-familiar, but invented example of his ~ o u n dmethod of experiment and the terminology as they proceeded. Thus when accurate grasp of the nature of colloids. they proposed new terms, as was done by Selmi I t would be easily porrible t o multiply quoand Graham, they stated exactly their significance tations of striking interest from the papers and the reasons for adapting them. Again. they reproduced. It must suffice to thoroughly reeomwere not encumbered with pre-exi3ting theorie~, mend the book both to beginners in colloid but were meeting and creating new faets and a chemistry and to m0readv;meed students. They new technic with unprcjudieed vision. should both derive profit from its perusal. The papers which are reprinted in this edition The appearance of the book is dignified and i t is cover wideranpe, extending as they do over the printed on a rough paper, whieh maker i t comphysiological chemistry of fats and proteins, the fortable to read, although the type shows aceapreparation and properties of inorganic hydrosional degradation. The tran~lationrappear t o sols, the properties of hydrogels in regard t o be very happy and i t is very seldom that an water, and the general properties of colloidal awkward phrasing may be noticed. The editing systems. some of these, such as the paper of this selection was entrusted to Mr. Emil "On the Experimental Relations of Gold (and Haeehek, the well-known colloid chemist. and Other Metals) to Light," by Michael Paraday, both he and his colleagues are to be heartily the one by Van Bcmmeleo "On the Nature o i congratulated upon t h e issue. Colloids and their Water Cootent." and that, S. E. S H ~ P F A X D "Om the Properties of Silicic Acid and other Andogour Colloidal Substances," by Graham, are The Teaching of Science and the Science Teacher. already elasnics of ~olloid chemistry. Others. The Relationshio of Science Teachine - to Hdu. notably Francesco Selmi's "Studies on the Decation in General, with Especial Reference to mulsion of Silver Chloride" and the "PseudoSecondary Schools aod the Upper Elementary Solutions of Prursian Blue," and Aschersoo's Grades. HHneenT B n o w n e r ~A N D FXAWX B. "Physiological Utility of the Fats" ere fundaW ~ H The . Century Company, New York mental papers, which have been over-looked till 322pp. 13.5 X 20.5 and London. 1925. xi recently and whieh equally deserve the title of em. $2.00. classic$. The object of the British Association Committee on Colloids in drawing attention t o As stated in the preface "this book is an outthe work of these early pioneers should be greatly growth of the experiences of the autham-one helped by this book, which will arrirt in broadenas head of a reienee department (Chemistry) in a large city system and the other for many ing the historical foundations of the science. The editor in the preface rightly calls attention years engaged in fitting students to teach hlght o the "strikingly modem viewso a i Archerson school sciences." Part I deals more specifically on adsorption and membrane formation, which with method. The authors draw from their rich (P. 24) he regards a. "a physical property, as a experiences and present many helpful ~uggestions
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