700 SUJniABY OF CUERENT RESEARCHES RELATING TO 



in the block Tc (fixed to the movable plate), so that the cutting surface 

 of the object in the clamp can be presented more or less obliquely to 

 the blade of the knife. The binding screw I fixes it in the various 

 positions. The clamp may be turned down so far as to allow the 

 object to be removed without coming too near the knife. If required, 

 a box is provided as well as the clamp, in which delicate objects may 

 be imbedded. 



Fig. 165. 



Dr. Korting considers the fixing of the clamp a most essential 

 improvement. When perfectly fixed, it stands oflf at such a distance 

 that a vessel can be placed underneath so as to catch all the drops 

 that fall, without wetting the other parts of the instrument or the 

 hands, &c. This is very important for those who work in the 

 house. 



Preparing Coal Sections. — Professor P. F. Eeinsch gives the 

 following directions for prepariug sections of coal : * — 



A plane cut, as in rock and mineral sections, generally is not 

 serviceable ; the cut jnust be made in relief. Thus only the difierent 



* See transl. in Amer. Natural., xv. (1881) pp. 498-9. 



