BACTERIOLOGY IN A NUTSHELL. 



Cleanliness. 



The 

 Skin. 



Its 

 Fortifications. 



We- have said in another chapter that bac- 

 teria exist everywhere. Our skin, finger-nails, 

 hair follicles, etc., all harbor them. Theii 

 numbers are limited only by the cleanliness ol 

 the individual and even on the surface of the 

 bodies of the most cleanly the existence of some 

 pathogenic bacteria is a normal condition. 



It has long been an open question whethei 

 or not micro-organisms found upon the skin 

 can gain admission, find their harmful camping 

 ground and bring about diseases unless the skin 

 has a broken surface, or is in some way injured. 

 In some instances it has been proven that in- 

 jury or abrasion is not always necessary in 

 order that germs of disease penetrate the skin 

 and do us harm. Entrance through an abso- 

 lutely unbroken skin is a rare occurrence, how- 

 ever, and then it is believed that the portal of 

 entry is either through the openings of the 

 sweat glands or the hair follicles. When in- 

 vasion takes place, we find as a result that such 

 troubles as pustules, boils, carbuncles, etc., 

 caused by pus-forming bacteria arise. As a 

 rule, while the sebaceous glands, which are the 

 appendages of the hair follicles, do not secrete 

 germicides, the perspiration is of an acid 

 nature, believed to be slightly germicidal and 

 it also contains salts which cause it to be an 

 enemy not easily overcome by certain forms oi 



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