167 



was examined microscopically, the grains were seen to have under- 

 gone considerable alteration, evidently produced by the solvent 

 action of a ferment, and the explanation of this was that in all 

 probability there had been used in the production of this starch 

 potatoes which had commenced to sprout. Again, in a case of 

 incendiarism, where a man suspected of the crime was found to 

 have in his possession a piece of cord apparently similar to that 

 discovered to have been used to set fire to the building, it was 

 conclusively shown that the two pieces were not really the same, 

 as one of them consisted of two strands of hemp and one of jute, 

 while the other was wholly of hemp. Many other examples are 

 given, but the two quoted will serve as specimens. 



Taking all the features of the book into consideration, not for- 

 getting the many excellent figures and the abundant references 

 to the literature of the subject, we have no hesitation in recom- 

 mending the work to all those who have to, or would like to, use 

 their microscopes either constantly or occasionally for technical 

 ends. 



The issue of a translation of the work would, we have reason 

 to believe, be much appreciated in this country. D. J. S. 



Die mikroskopische Analyse der Drogenpulver. Ein Atlas 

 fiir Apotheker, Drogisten und Studierende der Pharmacie. 

 By Dr. Ludwig Koch. 11 1 by 8| in. Vol. I., 16S pages, 

 14 plates. Leipzig, 1901 : Gebriider Borntraeger. Price 

 12 marks. 



It is not so very long ago that the " chemist and druggist " 

 powdered many of his drugs directly from the raw material, and 

 he was then able to judge pretty accurately of their quality. But 

 now he can often only obtain them in a powdered state ; with the 

 result that, although he is still responsible for their purity, he 

 has no check upon the wholesale dealer, unless he can tell from 

 the microscopical characters whether the powders sold to him are 

 what they pretend to be or not. It is Avith a view to provide 

 him with an absolutely reliable guide in this matter that Professor 

 Koch, of the University of Heidelberg, has planned the present 

 elaborate work. The first volume has been completed (it was 

 issued in three instalments), and it deals with the barks, or more 



