BLEEDING, WOUNDS, AND DISEASE GERMS 



73 



the person lies down and holds the limb straight up in the 

 air. In nosebleed, the person should sit up so that the 

 blood will not run to the head. If he presses the nostrils 

 together and breathes through his mouth, the bleeding will 

 soon stop. Then he should not blow the nose for some 

 time, so that the clot may have time to get thick and 

 surely stop the bleeding. 



135. Injury to cells. The cells of the body are always 

 likely to be hurt, and yet they quickly mend themselves 

 again. They are hurt by cuts, scratches, burns, and 

 bruises. A blast of cold air upon a heated part of the 

 body hurts the cells. But wounds are soon mended if we 

 do not take cold in them. We must explain what taking 

 cold is. 



136. Bacteria of disease. There are tiny living beings 

 called bacteria which grow everywhere in dead matter. 

 They produce decay, 



and change dead bodies 

 to a form which plants 

 can use as food. With- 

 out them, dead bodies 

 would accumulate and 

 cover the earth. But 

 a few kinds can live in 

 the lymph between the 

 capillaries and the cells 

 of the body, and there 

 produce diseases. A 

 few of these seeds or 

 germs of disease are 

 everywhere in the air, 



water, and soil, but there are very many in all 'kinds of 

 dirt and filth. A pin point can carry thousands of these 



Bacteria growing in the mouth ( x 400) . 



The specimen was obtained by scraping a 

 healthy mouth. 



a nucleus of an epithelial cell. 

 b different forms of bacteria. 

 c outline of an epithelial cell. 



