MATERIAL OF THE FRAME. 45 



about, and finally be crushed down, under the 

 great weight of the body ? Most certainly 

 they would. 



But there are several other important uses 

 of bones, which might be mentioned. Some 

 of them you would not understand very well, 

 however, till you know more about muscles 

 and tendons. I will, therefore, omit them. 



GROWTH OF BONE. We are not born with 

 the bones as hard as they are after we begin 

 to walk and run about. At first, many of 

 them are very soft ; and a large number are in 

 several pieces, with cartilage or gristle between 

 them. After a few years, they grow firmly 

 together. The bones of the head, in particu- 

 lar, are at first separate; and, without doing 

 any mischief to the soft brain within, will move 

 a little. But after we become older, and the 

 whole skull becomes firm, it would require a 

 very considerable force to move them ; and 

 the consequences of moving them would be 

 dangerous. 



There is undoubtedly life, as it is often 

 called, (though we hardly know what life is,) 

 in bones ; but while we are well, there is not 



