ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 431 



a spindle with eccentric pin passes through the bore in thef bridge and 

 transmits the rotation of the motor which has been conveyed by a cord 

 pulley countershaft to both bridge and tripod. The speed has been kept 

 so low that no tilting effect is produced in the triix)d ; the speed 

 obtained by hand-movement having been taken as a model. Only the 

 crystal should move in the grinding material. Some oil or vaseline is 

 applied V)eneath the screws and feet of the tripod and bridge. During 

 work the grinding-plate may l)e moved sideways so that it is used on as 

 many points as possible. The rules for making specimens are otherwise 

 as usual. For measuring, the tripod is lifted and placed on the hori- 

 zontal bracket. After some practice the operator will know how long 

 the machine must be left running to grind down a given quantity from 

 the specimen. The poHshing is carried out in an analogous manner. 

 By the aid of this attachment it has been possible to grind quartz prisms 

 with a refractive angle of 10° at the edge down to xof o i^^^- thickness, 

 and polish them. Experiments with iron glance prisms have also proved 

 the efficiency of the attachment, as with these prisms a manual guiding 

 proved unsatisfactory. 



(4) staining- and Injecting-. 



Demonstrating Intracellular Inclusions in Articular Rheuma- 

 tism.* — F. J. Bosc and M. Carrieu make smears on slides from the 

 joint-fluid, and also use the clot after it is set on coohng. The clot is 

 immersed in acetic-suljlimate or in alcohol, and when fixed paraffin 

 sections are made. The bodies found in the cytoplasm of some of the 

 cells are eosinophilous and best stained by Giemsa. The bodies are 

 of varying size, and the authors consider them to be of a parasitic 

 nature. 



In a later communication the authors state that they have found 

 similar appearances in the large mononuclear leucocytes of the blood 

 in acute rheumatism. 



Staining Properties of the Tetanus Bacillus.t — The familiar 

 text-book statement, defining this organism without qualification as 

 Gram-positive, has long been recognized as misleading. H. Eymer 

 has examined a number of strains of the bacillus, as well as a variety 

 of material from infected animals and other sources, and finds that the 

 majority of bacilli do not retain the stain when treated l)y this method, 

 while only a few isolated individuals are retentive of the violet colour. 



Demonstrating Nerves in Mammalian Ovaries. | — In this in- 

 vestigation W. Abel and A. Louise Mcllroy used the silver nitrate 

 method of Ramon y Cajal. There are several modifications of this 

 method, but the first modification was found to be the most successful. 

 It is carried out as follows : The tissue, which is divided into small 

 blocks of from 2-4 mm., is placed for 21 hours in a bath of 65 p.c. 

 alcohol with • 75 p.c. ammonia, at a temperature of 32' C. . . . It 



* C.R Soc. Biol. Paris, Ixxiv. (1913) pp. 1262-3, 1322-3. 



t Centralbl. Bakt., Ite Abt. Orig., Ixix. (1913) pp. 1-5. 



i Proc. Roy. Soc. Med., vi. (1913) (Obstet. and Gynaec. Sect.) pp. 240-7 (4 figs.). 



