145 



SIDE y/£W 



THE PYRAMID fS ADJUSTED 

 HORIZONTALLY 



CE OF 

 QUID 



TROUGH AND 5TEEL 

 PLATE IN CROSS 

 SECTION. 



PLATE 



Fig. 264. Pyramid and part of trough, side view. 



trough, grouping themselves into wreaths, strips, or small flocks. If there 

 is too much liquid they will disseminate and, furthermore, water will pos- 

 sibly adhere to the pyramid. Inspection of the sections through the micro- 

 scope will be rendered difficult or impossible by disturbing light refraction, 

 resulting from an exaggerated convexity of the surface of the liquid etc. 

 Occasionally, the sections will roll themselves up on the surface of the 

 liquid, but they will regain their original shape if allowed to float in the 

 trough for a few minutes before fishing up. — The above methods of embed- 

 ding, cutting of pyramids, grinding and sectioning have been recommended 

 by, i.a., F. S. Sjostrand, Karohnska Institutet, Stockholm. 



Thefishing-up oj the sections 



The sections are fished up from the trough with a thin, fine-pointed, 

 soft brush, and transferred to a sUde which has been thoroughly cleansed 

 (albumin glycerine is not used). A drop of alcohol (20 per cent) is placed 

 on the centre of the sUde. The brush is then inserted into the liquid and 

 slowly pushed towards that part of the knife where the sections are as- 

 sembled. When the tip comes under the sections the brush is carefully 

 lifted up over the surface of the water, turned upside down, and allowed 

 to touch the surface of the liquid on the slide. At this stage a preUminary 



