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JAMES CLEKK MAXWELL. 

 II. MELOID AND APIOID. 



[CHAP. iv. 



If a point C move so that m CA ~ n CB = a constant quantity, 

 it will describe a curve called a meloid when m CA > n CB, and an 

 apioid when n CB > m CA. The points A and B are called the foci. 



PROPOSITION 1 PROBLEM. 

 To describe a Meloid, Fig. 1, or Apioid, Fig. 2. 



Take a rigid straight rod AD, centered at A. At D erect a small 

 cylinder upon the rod, and also another at B on the paper. Then take 

 a flexible and inextensible thread of such a length that m AD n times 

 the thread = constant quantity; then wrap the thread round B and D and 

 a movable cylinder C, so that there may be n plies between B and C, 

 and m plies between C and D ; if now AD be turned round and the 

 thread kept tight, the point C will describe a meloid or apioid. 



