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A YEAR IN SCIENCE 



have not become sufficiently stiffened to resist the pres- 

 sure of the weight of the body. Round shoulders often 

 result from a careless position of the body. 



Some germ diseases also attack the bones, among 

 them tuberculosis, which sometimes causes a deformity. 

 A common cause of deformity of the bones in small 

 children is lack of the proper kind of nourishment. 

 Lime salts are necessary for stiffening the bones, and a 



From Blount, Physiology and Hygiene, Row, Peterson & Co. 

 Fig. 175. Fractures; A, a "green stick" fracture of the radius; 

 B, a fracture of the tibia. 



lack of these salts in the food results in a disease called 

 the rickets, which causes weak and crooked bones. 

 In a fracture the bone is broken. To treat a fracture, 



