ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 113 



of temperature. The heat is applied by a steam coil between the outer 

 and inner covers. In the top, hottest compartment, the coil is closer 

 than in the lower cooler chambers. The coil is shown in fig. 2S. The 

 embedding apparatus is contained in the middle chamber. This is pro- 

 vided witli a cooling jacket, connected with a cold water supply controlled 

 by tlie tap H. The steam is supplied from a small kettle, to which access 

 of gas is controlled by the regulator R. In this the gas valve is closed 

 by the expansion of a U-shaped metal bar. The lowest and coolest 

 compartment is provided with trays, and is suitable for the treatment 

 of sections. 



(4) Staining' and Injecting-. 



Injection of Lymphatic Vessels.* — H. Baum has made a study of 

 the lymphatic system of cattle, and has in previous communications 

 given an account of his methods. In the present paper, he gives 

 references to his former work, and mentions one or two points of im- 

 portance in the technique of carrying out injections for the purpose of 

 demonstrating these vessels. The author makes use for most purposes 

 of a narrow metal cannula, 0*29 mm. in diameter. For the penetration 

 of firm tissues this is superior to glass. For injecting the vessels of 

 l)ones, except in the case of young animals, previous boring is necessary. 

 Tiie author further describes the methods of demonstrating, lymphatics 

 in the perirenal fat and in tendon sheaths. It is important for all work 

 of this kind that the material should be absolutely fresh. 



Demonstration of Tubercle Bacilli in the Blood. f—Y. Suzuki 

 and Z. Takaki make use of the following method. One c.cm. of blood 

 drawn from a vein is mixed with 2 c.cm. of sodium citrate. The 

 mixture is shaken, and 5 c.cm. of 1 p.c. acetic acid is added to it. The 

 red corpuscles become lysed, and the solution assumes a pale red colour, 

 which darkens after two minutes standing. After centrifuging this 

 mixture for ten minutes, the clear supernatant fluid is poured away, and 

 to the sediment is added 10 c.cm. of 30 p.c. autiformin. These are 

 well mixed together, and warmed for about three minutes. Then the 

 mixture is centrifuged, the sediment washed with distilled water, and 

 again centrifuged. The sediment now is greyish in colour, and of very 

 small bulk. It is spread as a film upon a slide, fixed, and stained by the 

 Ziehl-Gabbet method. 



Rocking Staining Plate.|— B. Galli-Yalerio describes a small piece 

 of apparatus which may prove useful in staining films with Leishman's 

 stain and others which yield precipitates. It consists of a plate, 

 16 cm. square, attached to a wooden box containing clockwork. By 

 means of this mechanism a gentle swinging movement is imparted to 

 the plate. The slides to be stained are set out on the plate, which is 

 set in motion. The stain is dropped upon the slides. The movement 

 causes the stain to be distributed evenly upon the slide and prevents the 

 formation of precipitates. 



* Anat. Anzeig., xl. (1911) pp. 303-9. 



t Centralbl. Bakt., Ite Abt. Urig., Ixi. (1911) T^p. 151-2. 



J Centralbl. Bakt., Ite Abt. Orig., Ixi. (1911) pp. 190-2. 



Feh. 21st, 1912 i 



