THE X RAYS. 



IIZ 



in a similar position to that above described against an uncovered 

 sensitive plate in a dark room and then lighting a match. By the 

 last method we should obtain a true shadow of the hand, the flesh 

 would throw as dense a shadow as the bones, and the latter could 



M 

 C 



c 



not be detected in the general blackness. In the cathode photo- 

 graph, on the other hand, a difference in absorptive power is 

 shown : the flesh looks like a hazy film around the skeleton, and 

 even the medulla cavities can be made out, and the varying thick- 



