158 SCIENCE PROGRESS 



hands cannot secure quite the same uniformity of treatment and sense of 

 continuity that is possible where the entire work has been written by one man. 



The only trouble is to find the man. Dr. Mellor has solved this part of 

 the problem satisfactorily, and has undertaken to settle the other difficulties 

 by himself compiling a whole treatise on general chemistry from start to 

 finish. 



It is difficult to know whether one feels the more amazed at Dr. Mellor's 

 audacity in setting himself the task of composing a general treatise on 

 chemistry, or at the extraordinary patience and perseverance which have 

 enabled him to complete already two of the six or seven volumes which are 

 promised. 



He aims at describing all the compounds known in Inorganic Chemistry, 

 and, where possible, these are discussed in the light of the so-called Physical 

 Chemistry, which Dr. Mellor quite rightly regards as a branch of general 

 chemistry, and not as a science in itself, as some of its devotees would have 

 us beheve. 



The work is intended to cover a larger range of facts described in greater 

 detail than can be found in any work liitherto published, together with 

 copious hsts of references which will be of very great value to all chemists, 

 both academic and industrial. 



The first volume is largely of an introductory character, dealing with the 

 early history of chemical philosophy and including a general discussion of 

 various physico-chemical conceptions such as thermodynamics, the phase 

 rule, electro-chemistry, and so on ; in addition, hydrogen and oxygen and 

 their compounds are described in detail. 



Vol. II covers the halogens and the alkaU metals and ammonia, and 

 it is intended that Vol. Ill shall deal with copper, silver, gold, the alkahne 

 earths, radio-activity, and the structure of matter, whilst later volumes will 

 be set aside for the remaining elements arranged for the most part according 

 to the periodic law, though Dr. Mellor disavows any bhnd faith in the law 

 as a perfect scheme for classifying chemistry. 



Occasionally one has a faint suspicion that Dr. Mellor's pen has run 

 away by itself, as, for instance, in the httle moral lecture on p. 358, Vol. I, 

 on Not Placing Too Much Trust In Words ; it is all very true, but the only 

 question is whether a treatise on Chemistry is quite the right place for such 

 little homilies. Again, the quotations at the head of each chapter, although 

 excellent, are perhaps a Uttle out of place in a cold, calculating textbook. 



Yet, after aU, they are but the expression of the individuality of the 

 author, and a chemistry book should be something more than a mere soulless 

 card-index of disconnected facts, and if the quotations do not help greatly 

 to the understanding of the contents of the chapters, they serve to remind 

 one of the fact that the book is permeated with the personality of the author. 



If Dr. Mellor can keep the remaining volumes promised up to the standard 

 which he has set in the present ones, he will have aclueved something like a 

 record, and created a work of which not only author and pubUshers may be 

 proud, but which we shall feel to be a real credit to British Chemistry. 



F. A. M. 



Laboratory Exercises in Applied Chemistry for Students in Technical Schools 

 and Universities. By Dr. Wilhelm Moldenhauer. Translated 

 by Lawrence Bradshaw, D.Sc, Ph.D. [Pp. xii + 226, with 36 

 figures.] (London : Constable & Co., 1922. Price 12s. 6d. net.) 



This book is essentially a " practical " work, and is intended chiefly for 

 students at technical colleges and the hke who will be going into the chemical 

 industry later. 



Not only is care taken to explain the nature of the reactions involved in 



