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Mr. Lubbock on the Heat of Vapours 



ON THE CONDITIONS OF THE ATMOSPHERE, 

 AND ON THE CALCULATION OF HEIGHTS BY 

 THE BAROMETER. 



The same principles are applicable to the constitution of the 

 atmosphere ; but we are far from possessing such extensive and sa- 

 tisfactory data for testing the accuracy of the formulae. The best 

 observations for this purpose are those of M. Gay Lussac, recorded 

 by M. Biot in the Connaissance des Temps for 1841, in the follow- 

 ing table. 



Table des observations par ordre de hauteurs barometriques. 



I shall employ the 1st, 5th, and 21st observations for the deter- 

 mination of the constants, and I propose then to calculate with these 

 constants the temperatures corresponding to the intermediate obser- 

 vations. As the pressures are proportional to the heights of the ba- 

 rometer, if the variation of gravity be neglected we may take the 

 heights of the barometer to represent them, and we have 



