166 



Altogether Miss Newbigin is to be congratulated upon the 

 freshness with which she has treated a well-worn subject, and our 

 only regret is that a rather larger number of illustrations could 

 not have been sandw^iched into such admirable text. D. J. S. 



Lehrbuch der technischen Mikroskopie. By Dr. T. F. 

 Hanausek. 10 by 6| in., x + 456 pages, 256 figures 

 in the text. Stuttgart, 1901: Ferdinand Enke. Price 

 14 '40 marks. 



There is every indication that the employment of the microscope 

 for all kinds of technical purposes is rapidly assuming more and 

 more importance, and the issue of a text -book on technical micro- 

 scopy therefore, by such an expert as Dr. Hanausek of Vienna, 

 will certainly meet with approval. The work before us is some- 

 what ambitious, in that it claims to cover the whole field of 

 technical microscopy Although we may well be scejjtical on this 

 point, looking to the almost inexhaustible variety of the questions 

 connected w4th commerce and the arts which are decided w^holly 

 or partially by the microscope, the book is undoubtedtly a most 

 comprehensive one. And not only does it range over a wide area, 

 but the subjects touched upon are, for the most part, treated 

 in sufficient detail to make the book really serviceable to the 

 practical man, w^hich, we need hardly say, is by no means 

 always the case with text-books. 



Of the varied contents it is not easy to give a brief summary, 

 but it may be pointed out that by far the greatest amount of 

 space is devoted to vegetable substances such as starches, cotton, 

 flax, hemp, jute, woods, barks, roots, leaves, fruits and seeds. 

 The animal fibres (wool, hair and silk) and bone, ivory, horn, etc., 

 are, of course, also considered, though more briefly, and there is 

 a final chapter upon micro-chemical analysis. Two extremely 

 instructive sections are concerned wdth the microscopical examina- 

 tion of paper and textile fabrics. The author has also drawn 

 upon his own experience as a technical microscopical referee to 

 include a number of interesting examples of actual problems 

 which have occurred in practice. For instance, a particular 

 sample of potato starch was found by the manufacturer to be 

 unavailable for the preparation of dextrine. When the starch 



