CHAPTER IX 



A STUDY OF THE SKELETON 



X-Ray Pictures. One of the marvelous discoveries of the 

 closing years of 

 the last century 

 was that of the 

 so-called X-rays. 

 If, when a sen- 

 sitive photo- 

 graphic plate is 

 held in position 

 behind a man, 

 these electrical 

 rays are focused 

 upon any part of 

 his body the 

 hand for in- 

 stance, a picture 

 is produced on 

 the plate like 

 that shown in 

 Fig. 62. One can 

 see the faint out- 

 lines of the hand, 

 and within it a clear picture of the bony skeleton that forms 

 its framework. 



The Uses of the Bony Framework of the Body. In certain 

 regions of the body, bones surround and protect delicate 

 organs. The brain, for example, is inclosed within a bony 

 box ; the eyes are set into deep sockets ; the delicate mech- 



159 



FIG. 62. X-Ray Picture of the Hand. 



