observed at any other Temperature. 261 



calculations having been made to nine places of decimals, the 



seventh figure will be correct. If 



a = linear expansion of glass ... = jsloo^^"^'' ^^^^^ degree of 



b = cubical dilatation of mercury = yJjo V''^ centigrade scale. 



h = observed height of the barometer. 



/ = the temperature by the centigrade scale. 



K= h when reduced to 0° of the same scale. 



k' 



/I + at \ _ 



h m 



+ bty 



log A' = log h + log m. 

 In the following Table m and its logarithm are given for 

 each quarter of a degree of the centigrade scale between —12 

 and +52. 



Hayes, Kent, March 1, 1832. 



