892 



SUMMARY OF CURRENT RESEARCHES RELATING TO 



is easy to examine the preparation under the Microscope before 

 cutting ; the smallest details can be distinguished, and with a low 

 power the object can be arranged very accurately, and the section can 

 be made exactly through the desired point. 



The sections being thus made, they are placed on a glass or a 

 very dry surface, then taken up with a needle or fine moist brush 

 and placed on the slide in a drop of water ; the gum dissolves and 

 leaves the preparation in place. A drop of glycerine placed at a 

 corner of the cover-glass, quickly penetrates under it and replaces 

 the water (which evaporates), and mixing with the melted gum, 

 forms an excellent preserving liquid. 



Roy's Microtome.* — Dr. C. S. Eoy describes a microtome 

 (Fig. 163) for cutting frozen or otherwise hardened substances. 



The knife Ji is connected with the metal bar c by the clamp g. A 

 small piece of leather laid on the back of the knife at the place where 

 it is held by g enables the section to be made at any desired angle to 



Fig. 163. 



the horizontal. By a handle n the bar c can be moved on the pivot e 

 furnished with the milled head /. The pivot passes through the 

 support b which is attached to the base plate a. The knife is thus 

 able to move over the object plate d, describing a circle on the pivot e. 

 The object plate may be raised or lowered by k, and its under surface 

 is deeply fluted, with the object of diminishing the thickness of the 



* Arch. f. Mikr. Anat., xix. (1881) pp. 137-43 (1 pi.). 



