102 LECTURES TO SCIENCE TEACHERS. 



(Cl), which we have already seen. This train has some 

 practical applications in machinery, hut is not very often 

 used. 



Here then we have ohtained from one and the same chain 



four entirely different mechanisms, all of them more or less 

 familiar. The method we have adopted has again heen 

 successful in making the real relations of these apparently 

 dissimilar things perfectly ohvious. 



