MICROSCOPE IN-DOORS. 59 



CHAPTER VI. 



A HALF-HOUR WITH THE MICEOSCOPE 

 IN-DOORS. 



FOR amusement and instruction with the Micro- 

 scope, we need scarcely stir out of our rooms. The 

 very hairs on our head may be made objects of 

 interesting investigation, and especially if we com- 

 pare them with the hairs of other animals, and the 

 appendages generally of the skin. The fine outer 

 coating of the skin is composed of minute scales, 

 which are flattened cells, and may be easily ob- 

 served by scraping a portion of the skin on to 

 a glass slide with a drop of water on it. The nails, 

 the hairs, and other appendages of the skin, are 

 composed of the same kind of scales, or cells. 

 These cells are developed in little pits, or follicles, 

 from which the hair is projected, as it were, by 

 their growth from below. Under a low power the 

 cells of the human hair cannot be observed. It pre- 

 sents, however, a well-marked distinction between 

 the outside, or cortical layer, and the interior, or 

 pulp. The latter, by a high power, especially if 

 the hair has been first submitted to the action of 

 sulphuric acid, will be found to contain cells more 

 or less spherical, whilst the former contains cells 

 more or less flattened. These project a little 

 beyond the edge of the hair, so that its sides are 

 not quite smooth (Fig. 179, PI. 7). By placing a 

 hair between two pieces of cork, fine transverse 

 sections of it may be made by means of a sharp 

 razor, when the pulpy portion will present a dark 



