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of the lower barometc; the remainder will give a logarithm 



which will denote the natural number, which expreffes the 



height at which the mercury will fland in the upper baro- 

 meter. 



But, 3tio. The height of the mercury thus obtained is only 

 that which it would have in temperature 32°. To obtain its 

 height in the adual temperature above, w-e mult add to the mer- 

 curial height thus found its ^r^* P^''^ multiplied into the funda- 

 mental difference, viz. the difference of the temperature above 

 with 32^*. 



Note. The fupplemental height will generally be obtained more 

 eafily by multiplying the fundamental difference into the loga- 

 rithmic refult, and dividing the produd by 400. Or if Schuck- 

 burg's coefficient be preferred, by 41 1. 



* This coefKcient I take from that great treafure of mathematical knowledge Dr. 

 Hutton's Dictionary, article Barometer. 



Examples. 



