158 SCIENCE PROGRESS 



of alcoholic fermentation ; lastly, the chemical changes involved in fermentation 

 are discussed in the seventh chapter, the mechanism of fermentation in the eighth. 



Here and there a few obscurities in language are to be met with ; these, it 

 may be hoped, will be removed in a later edition. Thus (p. 85) we read : " This 

 enolic form is capable of giving rise to all three hexoses and the change by which 

 the enolic form is produced and converted into an equilibrium mixture of the 

 three corresponding hexoses is catalysed by alkalis or rather by hydroxyl ions." 

 "Equilibrium mixture" is ugly, "catalyse" is a hideoqs and unnecessary verb ; 

 in what way are we to think of a change as "catalysed" or "loosened down" — and 

 why the "or rather by hydroxyl ions"? — why should we not be satisfied with 

 alkalis, which are real things ; why not leave alone hydroxyl ions, which are 

 mere metaphysical abstractions ; and if ions are to be spoken of in such a 

 connection, why leave out the poor sodium ion which has just as much right to 

 consideration as the hydroxyl ion in such a case, Faraday having taught us that 

 two opposite ions must be operative simultaneously ? There seems to be no end 

 to the absurdities that can be perpetrated in the name of ions : it is most 

 desirable that practical people like Dr. Harden, who have command of our 

 language, should set the example of using plain English when writing for English 

 students. The path of the student is sufficiently strewn with obstacles without 

 casting thorns upon it ; let any one who understands the subject consider the 

 difficulty a student would have in construing the three and a half lines 

 referred to. 



The chief feeling of the expert reader will be one of gratitude to Dr. Harden 

 for having brought the facts together so completely and conscientiously ; but 

 it is not to be expected that in a subject of such difficulty the meaning of the 

 results arrived at by various workers will at once find a proper interpretation. It 

 is only too obvious on turning over the pages of the book that we are but at 

 the beginning of the inquiry : we know that the process of fermentation can 

 be made independent of life, we know that it is an enzymic process, yet one 

 apparently in which a variety of agents are concerned : that is all ; at present 

 we cannot trace the process in any of its details. But this little all marks an 

 extraordinary departure from the views that were current and are current even 

 now that phenomena apparently so complex as are those of fermentation must 

 have their origin in the processes of life. 



We may hope that Dr. Harden will be able to shed yet further light on a 

 subject which he has made so peculiarly his own of late years. 



Lessons on Soil. By E. J. Russell, D.Sc. [Pp. xv + 115.] (The Cambridge 

 Nature Study Series. Price is. 6d.) 



This is the first volume of a Nature Study Series to be issued by the Cambridge 

 University Press and the Syndics are to be congratulated most warmly on their 

 successful beginning. It is a book to be read and pondered over not only by 

 children at school but by every intelligent person, young or old, who can take 

 the least interest either in gardening or agriculture. It is written by one who 

 knows what he is writing about and is able to express himself simply, clearly 

 and concisely. Nature Study will become of some value and not the farce it is 

 in too many schools, if a few such books as this can be produced and put into 

 children's hands and those of their teachers. The illustrations are exceptionally 

 good and numerous ; that on p. 13, it may be mentioned, is of the landslip near 

 Lyme Regis, Dorset, not of the slip in the Isle of Wight. 



