[ 284 ] 
fion which is infinite when AL— AB, 
now becomes more than infinite, the denominator 
being negative ; and there is no height in the at- 
mofphere, at which the denfity is the fame in both 
temperatures. Again, if L fall above the earth’s 
furface (as in fig. 4. and 6.), LD is not among the 
ordinates of either curve which reprefent denfities j 
and AL, being negative, the expreffion be- 
B A x AL 
comes — m+Tl 
which expreffes a diftance beloW 
the earth’s furface ; but whether L fall above or 
below the furface depends upon the {bate of theden- 
fity at A, and the temperature jointly. If the den- 
fity were to be greater, in the greater temperature, 
then the greater ordinate at A belongs to the greater 
curve (as in fig, 4. and 6.), and L is above the fur- 
face: but if the denfity be lefs, when the tempe- 
rature is greater, then, of the two ordinates at A, the 
lefs belongs to the greater curve, and L is below the 
furface (as in fig. 3. and 5.) ; and in this cafe, the 
place of the point L depends upon the magnitude 
of AN, and the proportion of HK to AK. If 
HK : AK — AN : AB, then L and B (in fig. 3. 
and s-) coincide,, and the denfities are the fame at an 
infinite height. If HK be lefs than to bear to AK, 
the proportion of AN to AB, AL will be greater 
than AB, and L will fall beyond B, and the den- 
fities are no where the fame. But if HK be 
greater than to bear to AK, the proportion of AN to 
AB, AL will be lefs than AB ; and in this cafe thre 
will 
