709 
the mean Denfit.y of the Earth . 
Then I05A= 103 x 20*io8{ = 2071*210 
I 02 B=I 02 x 2 0 *II 2 | = 2051*509 
586*71 inches = 48*893 
13 ft. 2 inch. = 13*167 
Hence a ft (unreduced) is 4 1 84* 7 7 9 
But iince 62 - 40 = 22, therefore the reduction for the 
Bate of the air is - 22 x yto V ooo x 4185 = -*989, which 
being applied to the above fum, there remains 4183*79 
as correfponding to the ftate of 6 2 0 of the thermometer. 
From this laft number deduct its part, viz. *232, 
and there refults 4183*558 for the correct length of the 
part #/3 as determined by this very accurate method; 
which is but about a foot and a half more than what it 
was found to be by the lefs accurate meafure by the 
chain, which is a nearer approach to an equality than 
could well be expected. 
To determine now the whole length of the bafe ay; 
by taking the whole fums there are found to be 146 a 
with 144B and 779*78 inches of the odd parts. 
Then 146 a = 146 x 20* io8|= 2935*890 
144B - 144 x 20 *ii 2 |= 2896*248 
779*78 inches - 64*982 
The fum or a y (unreduced) is 5897*120 
The 
