88 THE HOUSE I LIVE IN. 



joints of the wrists, and indeed many others, 

 sometimes move like hinges, but they perform 

 other and very different motions besides. 



Hip JOINT. But the most curious joints in 

 the human frame are what are called the ball 

 and socket joints. The more important of 

 these are at the shoulder and the hip. I will 

 show you a cut of that at the hip. 



At a you see the deep hollow or socket in 

 the bone, where the round head of the femur 



