ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 605 



•dextrose-broth fermentation tubes without preliminary incubation. This 

 broth was prepared with fresh meat, from which the muscle sugar bad 

 been removed by Smith's method, and to this sugar-free broth 1 p.c. of 

 dextrose was subsequently added. The broth was made neutral to 

 phenolphthalein. After inoculation with the water the tubes were in- 

 cubated at 38° C. for 48 hours, gas readings being taken at 24 hour 

 intervals. At the end of 48 hours all tubes showing the formation of 

 gas were removed from the incubator, cooled to room temperature, and 

 the absorption of CO., determined by the addition of a 2 p.c. solution of 

 NaOH. 



Method of Isolating the Typhoid Bacillus.* — E. Cambier noticed 

 that typhoid bacilli pass through the pores of coarse porcelain in times 

 proportionate to their motility, and also that the typhoid pass through 

 more quickly than other bacteria. This observation was applied to the 

 isolation of typhoid bacilli in the following manner. A bougie filter 

 containing the suspected water is immersed in clear bouillon aud in- 

 cubated at 38°. Directly the bouillon becomes turbid, a small portion 

 is pipetted off and cultivated on other media, such as milk, potato, etc., 

 and further tested by means of the serum reaction. In this way typhoid 

 bacilli have been easily detected in Seine and Marne water. The method 

 is also applicable to stools. 



In connection with this method the author states that the typhoid 

 bacilli isolated by the foregoing procedure were agglutinated only by 

 strong doses of very active serum. This, however, does not afford any 

 ground for contesting their typhoid nature ; for he has found that when 

 coli and typhoid bacilli have lived in association, the typhoid requires 

 a strong serum to agglutinate it, and the coli acquires the property of 

 becoming agglutinated by typhoid serum. 



Technical Microscopy.f — Prof. T. F. Hanausek's Text-book of Tech- 

 nical Microscopy is the first German manual which embraces the whole 

 subject since the appearance of Wiesner's Introduction to Technical 

 Microscopy in 1867. The reader is presumed to possess more than a 

 mere rudimentary knowledge of animal and vegetable histology, and of 

 chemistry, since this text-book appeals more to advanced workers, and 

 is made to comprise more information in a given space than could be 

 done if elementary principles had to be discussed. The work is divided 

 into two parts : the first deals briefly with the Microscope and its ac- 

 cessory apparatus, and with the necessary reagents ; in the second 

 portion is described the microscopy of the more important types of 

 raw material, such as starch, animal and vegetable fibres, stems, roots, 

 leaves, flower, fruit, seeds, bone, teeth, and horn. 



The last chapter deals rather curtly with micro-chemical analyses. 

 The volume is well printed and illustrated. 



Technology of Microscopic Metallography. X — Prof. Le Chatelier, 

 in the course of a paper full of practical details on the above subject, 

 describes a special Microscope made for him by Pellin, of Paris. Its 

 construction, with the complete illuminating apparatus, is shown in 



* Comptes Rendus, cxxxii. (1901) pp. 1442-4. 

 t Stuttgart, 1901, x. and 456 pp. and 25(3 figs. 

 % Metallographist, 1901, pp. 1-22 (19 rigs.). 



