400 MB- A- OATLEY ON THE CONIC OE FIYE-POINTIC CONTACT. 
The expression for J has just been given ; we have besides 
(^dh) D‘ti=-Q.a% 
where the values of Qj, Q. are given (ante. No. 27) ; we have thus 
58. 
iw 
” j{ (m — 1) H 
-iD^U 
- 
(m-ir 
and 
whence 
D’U = -^.Ha«, 
1 
'3 I m— 1 " (m— 1)H 
1 TTo-Jrl(firAWi 
and consequently 
A=^,(4'F-3nH), 
which agrees with the result before obtained, and thus tire present method gives the 
complete solution of the problem. 
