46 



general use a moderately hollow-ground razor is 

 used. Examine the edge under a low power 

 to see if any notches exist, if so they must be 

 ground out on a hone. A ' water of Ayr ' stone, 

 as long as possible, should be used and kept 

 absolutely free from grit during use. The stone 

 should be soft, capable of being scratched with a 

 pin, and as a lubricant water or filtered kerosene 

 oil may be used. After honing, the razor should 

 be stropped. On one side of the strop a minimum 

 amount of razor paste should be rubbed in 

 and the leather side should be kept scrupulously 

 clean and dry. If the razor is hollow- ground on' 

 one side only, it should only be honed on this 

 side. 



Examined under the microscope the edge 

 should now present a clear, sharp line. It may be 

 tested on a thin hair, which it should easily cut. 



Fig. 8. Simple Embedding Apparatus 



3. Embedding Appazatus.—A slab of metal 

 (copper), 12 X 3 X -J inches. Heat this at one 

 end, and place the vessel containing the paraffin ' 

 at a point on the slab where the paraffin is just 



