398 
PROFESSOR M. J. M. HILL ON THE MOTION OF FLUID, PART 
As positive values of e only are required, it is necessary to examine the relations 
between cb and f which will make e positive 
If 
/ cc~ + b 2 co\ 
X^w~f) 
CO 
f + ab)[f ab 
- CO 
CO 
< f < 
2 
ab 
e is positive. 
cb 
2 
ab 
e is infinite. 
2 
ab 
CO 
< / < 
2 
ab 
e is negative, 
cb 
? = 
2 
ab 
e is infinite. 
2 
ab 
cb 
< 7 < 
a 2 4-5 2 
e is positive. 
cb 
r 
. « 3 + 5 2 
a*b 2 
e is zero. 
a^ + b- 
A 
■SJ e- 
A 
oo 
e is negative, 
a%~ 
It the relation between cb and f is such as to make e positive, it is necessary to see 
whether the equation in e above is satisfied. 
a 2 + 6 2 © 
_^\_arbl_l 
d )\ 2 4 
f) -rfw 
&> 2\s 
a - 
/ a) 
_4_ 
f) aW 
b~ + e-- 
, s “- 2 
- V / 1 
a >\ 2 4 
f) 
