[ 282 J 
In the 2d cafe, L - 1£±£ D=tab. log. LD ; or, if t=q, 
L *= *■— D = tab. log. LD. 
In the 3d cafe, L=j=t^-iiD=tab.log.LD; or, if/— 7 , 
tp — qs 0 2 5 
L =f ~~ D = tab. log. LD. 
The formula in which ^ and t are equal, will 
be of particular ufe in the application of this theory 
to the atmofphere, of which examples will fhortiy 
be given. 
In Cafe 1, if ^ = o ; that is, if AH — B, 
AL = D x rP # 
s 
and L + Dxi+| = tab. log. LD. 
But if — o, AL — D “ T * y 
and L D x - — tab. log. LD. 
cor. The interfeftion of two logarithmic s being 
given, which have a right line given in pofition for 
their common ajymptote, and fubt an gents fever ally given 
in magnitude to find the point in the common ajymp- 
tote , through which the ordinate , drawn at right angles 
with the ajymptote , is cut by the curves in a given pro- 
portion , and to afiign the magnitude of each figment , 
is the converfe of the foregoing problem ; and the 
fame principles lead to its folution. For fuppofe 
A the point required. The proportion of AC 
to 
