to DoBor hutton’s Determination of the 
very fteep, and the other in which it is very flat, or a 
very fmall in refpedt of b or d. 
i 2. And firft let us fuppofe the triangular fedtion to 
be equilateral ; in which cafe the angle of elevation is 
6o°, which being a degree of fteepnefs that can fcarce- 
ly ever happen, this may be accounted the firft extreme 
cafe. Here then we fliall have d — 2b — ^a V ^ and the 
formula in Art. 10, will become s x : — + x x 
h. 1. + iz. f x h. 1. - 1 — ±- for the value of 
4 a — x 
the attraction in the cafe of the equilateral triangle, in 
which r is = V a z — ax + x*. 
13. Or if we take x — na , where n exprefles what 
part of a is denoted by x, the laft formula will become 
sax : 1 — \n— \ V 1 —n + n* + nx h. 1, 
+ 2 di 
n + 71 
x h. 1. h±A± 2 . _ .. 1 — li-1 f or the cafe of the equila- 
teral triangle. 
14. To find the maximum of the expreflion in the 
laft article, put its fluxion = o," and there will refult 
this equation 1 + 
i -f n 
V 1 — n + n z 
2h. 1. 
2 — n 2^/ 1 — n\ 1? 
3 n 
ih.l. 1 + - + + ” ; the rootof which is n =*251999. 
Which fliews that, in the equilateral triangle, the height 
from the bottom to the point of greateft attraction, is 
only 
