174 



NATURE 



[October 7, 1920 



larity, which have been applied so fruitfully in 

 aeronautics, receive attention in chap, xi., and 

 cover the ground rendered familiar to us by the 

 reports of the Advisory Committee for Aero- 

 nautics. 



The remainder of the book is conventional 

 hydrodynamics, and is a further reminder of the 

 lack of success which has attended the efforts of 

 mathematicians and others to solve the problems 

 of the motion of fluids under conditions resembling 

 those of normal occurrence. As a summary of 

 formulae the chapters have a value to advanced 

 students. 



Taken as a whole, the book is one to be re- 

 commended to those students on whom the future 

 developments of aviation will depend, for it con- 

 tains the fundamental theorems on which the 

 science of the subject rests and must continue to 

 rest for such period as we can now visualise. 



Text -books on Chemistry. 



(i) Treatise on General and Industrial Inorganic 

 Chemistry. By Prof. Ettore Molinari. Second 

 edition. Translated from the fourth revised 

 and amplified Italian edition by Thomas H. 

 Pope. Pp. xix -I- 876 -1- 2 plates. (London: 

 J. and A. Churchill, 1920.) Price 42s. net. 



(2) Trattato di Chimica Generale ed Applicata 

 all' Industria. \'ol. il. Chimica Organica. 

 By Prof. Ettore Molinari. Parte Prima. Terza 

 edizione riveduta ed ampliata. Pp. xix -F 624. 

 (Milano : Ulrico Hoepli, 1920.) Price 28 lire. 



(3) A Text-book of Inorganic Chemistry . Edited 

 by Dr. J. Newton Friend, Vol. ix. Part i. 

 Cobalt, Nickel, and the Elements of the Plati- 

 num Group. By Dr. J. Newton Friend. 

 (Griffin's Scientific Text-books.) Pp. xvii-t-367. 

 (London: Charles Griffin and Co., Ltd., 1920.) 

 Price 1 8s. 



(i and 2) pvR- ETTORE MOLINARI is pro- 

 l_y fessor of industrial chemistry at 

 the Royal Milan Polytechnic and at the Luigi 

 Bocconi Commercial University in the same city, 

 and his treatises on inorganic and organic chem- 

 istry are, apparently, mainly directed to the 

 special character of his teaching in those institu- 

 tions. Here chemical theory,_ in effect, is wholly 

 subordinated to practical application, and the 

 books are simply descriptive manuals of chemical 

 technology, adapted to the needs of polytechnic 

 students and suitable for general reading. They 

 may be said to occupy a position intermediate 

 between the general treatise on chemical theory 

 and the specialised handbooks on chemical tech- 

 nology. Prof. Molinari goes so far as to say 

 NO. 2658, VOL. 106] 



that his books reflect the change which has come 

 over the teaching of modern chemistry. In his 

 opinion the methods and spirit of the teaching 

 of Liebig, Hofmann, and Kekule no longer corre- 

 spond with present-day requirements. The 

 " beneficent impulse " which these great teachers 

 gave to chemical studies was, we gather, too 

 exclusively "scientific" and "theoretical." The 

 author, however, is a little unfortunate in his 

 argument. He could scarcely have selected three 

 names more alive to the utilitarian aspects of 

 chemical science, however mindful they might be 

 of the primary purpose of their calling and pro- 

 fession. The whole development of certain great 

 branches of applied organic chemistry may be 

 said to have sprung directly from the teaching 

 and example of Liebig, Hofmann, and Kekule. 

 Liebig 's genius ranged over practically the whole 

 field of the industrial chemistry of his day ; 

 Hofmann early threw himself, with characteristic 

 zeal and energy, into the newly created synthetic 

 colour industry, the enormous extension of which 

 is fundamentally based upon Kekuld's fruitful 

 conception. 



Prof. Molinari insists that "general chemistry 

 can no longer be a simple and arid exposition of 

 fundamental laws and of the properties of the 

 innumerable known substances, but should pos- 

 sess a soul which brings it into contact with the 

 vital activities around which it clings." "The 

 chemical text-books which have been used up 

 to the present time do not correspond sufficiently 

 with these requirements." "The present treatise 

 took its rise from these considerations, and has 

 no other pretensions than to be an attempt to 

 initiate a work of reform in the teaching of 

 chemistry." 



These excerpts are taken from the preface to the 

 first edition of the former of Prof. Molinari 's two 

 works cited above, in which the author sketches the 

 general plan of his work and makes his apologia 

 for its special character. In the preface to the 

 fourth Italian edition, on which the present 

 English edition is based, he enforces his point 

 of view. The Great War, he contends, "has 

 emphasised the necessity of developing chemical 

 teaching more and more along the lines of its 

 practical applications." Hence he has been led 

 "to treat the material still more from the indus- 

 trial standpoint." Various chapters have been 

 considerably enlarged, "certain improvements — 

 presumed or real — being indicated only by the 

 numbers of the patents in question, so that the 

 further details may be ascertained from the 

 journals of applied chemistry." Considering the 

 class of person to whom the work is ostensibly 



