I 4a8 1 



Second. 



Barometer being ''9,5, what is the length of a vertical co- 

 lumn of air that weighs as much as -rV of an inch of mercury ? 



Here the number next lower is 29,4. 



Then log. 295 = 469822 

 log. 294 = 468347 



14,75 fathoms. 



Here the prefTure being diminifhed the length is greater than 

 in the former Example. 



Barometer being 29,54, ^what is the length of a vertical 

 column of air that weighs as much as tV of an inch of mer- 

 cury ? 



fJere the number 29,54 — 0,1= 29,44. Then log. 2954z=4704io 



log. 29441=468938 



Length = 14,72 faths. 

 Four4h. 



-y 



