18 EVENINGS AT THE MICROSCOPE 



just thrice as thick as the hair that we have been examin= 

 ing, or yfoth of an inch in diameter. The sinuous lines 

 across the surface are proportionally far finer and closer 

 together, and no saw-teeth are visible at the edge, the most 

 delicate adjustment showing only a minute undulation in 

 the outline; that is to say, the overlapping scales are far 

 thinner, and therefore their terminations are nearer together 

 in the hair of the Swine than in that of Man. I will now 

 show you a transverse section of a similar bristle, which I 

 will obtain thus: I take this old brush, and with a razor 



HOG'S BRISTLE. 



cut off one of the bundles of bristles, close to the wood; 

 then I take off as thin a shaving as I can cut, wood, bristles, 

 and all: I repeat the same operation two or three times. 

 Now, picking out the shavings of wood, I take up a few 

 of the dust-like atoms with the point of my penknife, and 

 scatter them on this plate (or slide) of glass, and these I 

 cover with another plate of thin glass; for this dust is 

 composed of thin transverse slices of the bristles, and as I 

 scatter them, some will fall upon their cut ends, so that we 

 shall look through them endwise. 



Here is one, very suitable for examination since it is 

 not a whole section, the razor having passed somewhat 



