i;o SCIENCE PROGRESS 



A Compendium of Food-Microscopy, with Sections on Drugs, Water, and 

 Tobacco. Compiled with Additions and Revision from the late 

 Dr. A. H. Hassall's works on Food. By Edwy Godwin Clayton. 

 [Pp. xxxix + 406, with 282 illustrations.] (London : Balliere, Tindal & Cox 

 1909. Price 10s. 6d. net.) 



The valuable aid that the microscope offers in the detection of adulteration in 

 foods and drugs is now so well recognised that the appearance of a new work 

 dealing exclusively with this subject will be welcomed by analysts. The welcome 

 should be the more cordial as, although the title is new, the volume is practically 

 a revised and augmented edition of Hassall's Food : Its Adulterations and the 

 Methods for their Detection. Such a revision has long been a desideratum, and 

 in its preparation the author has had the inestimable advantage of having discussed 

 with the late Dr. Hassall the plan upon which it was to be based. 



On comparing it with Hassall's work it will be seen that the general arrange- 

 ment of the matter has been comparatively little altered. Nearly all the 

 original illustrations remain, but, being printed on a more suitable paper, are 

 distinctly improved : to these have been added new illustrations dealing more 

 particularly with animal parasites. The text has also undergone considerable 

 revision, but here, too, the original has been as far as possible retained. The 

 addition of a bibliography, that has been brought well up to date, distinctly adds 

 to the utility of a work which must form an indispensable addition to the analyst's 

 library. 



Notwithstanding these advantages a certain feeling of regret must be ex- 

 pressed that the treatment of the various substances has not been brought more 

 nearly abreast of the times. Comparatively little account has been taken of the 

 progress made during the past twenty years in the knowledge of the anatomy of 

 foods and drugs and the methods adopted for examining these and their powders. 

 Instances of this are to be found in the defective descriptions of the various flours, 

 of pepper, cayenne, cardamoms, etc. Improved methods of clearing the tissues 

 have facilitated the observation of minute details, and have resulted in the 

 production of more accurate illustrations and in the detection of more refined 

 adulterations. These methods and their results find, unfortunately, no place in 

 the work, the author professing to regard them as unnecessarily elaborate. 

 Hence no attempt has been made to advance the microscopical examination 

 beyond the stage to which Hassall carried it. The adulterations cited and 

 illustrated are, with few exceptions, those described by Hassall, many of which 

 the author himself admits are extremely unlikely to be met with, while others of 

 everyday occurrence, such as powdered almond-shells, olive-stones, exhausted 

 drugs and spices, etc., are either passed over or receive, at most, the briefest 

 mention. An outline of the methods suitable for the examination of nut foods 

 and the means by which their identification and purity may be established would 

 have been very acceptable. The mere statement that the aleurone grains of the 

 Brazil nut are large is surely insufficient, and the illustration affords but little help. 

 This is the more to be regretted as, during the last few years, increased attention 

 has been paid to the characters of the aleurone grains as a means of identifying 

 such substances, and many have been accurately described and figured. Bombay 

 mace is mentioned as a sophistication of Banda mace, but no hint is given of the 

 means by which it may be detected. Pepper, that most important of powdered 

 spices, is similarly insufficiently treated. 



It is sincerely to be hoped that a new edition of so useful a work may soon 



