M| 



ce (9) give* 





therefore, by integration, 



' 



" 



; *- 



:.. ..(5). 



COS^fr X C 



nstant is rojuir -^ration if we suppose the 



ugh the lowest point of the curve, for 

 there ^-0. 



From (4) we may deduce 



**(! + *.*)*!-*' ..... (6); 



therefore, by integration, 



..... (7). 



4 required in the integration if we suppose the 

 u of co-ordinates to be at the distance c below the lowest 



. 



17 a 



