M. KupfFer on Iso-geothermal Lines. 



253 



of the formulae of Dr Brewster, which necessarily carry the 

 isothermal lines round two separate poles. 



The following is the general table given by M. KupfFer. 

 We have not converted the degrees of Reaumur into those of 

 Fahrenheit, because it is the comparison of the two columns 

 with which we are principally concerned. 



Heieht in T^'^P^^'^t^ures observed 

 Places. Latitude. ™ ^ „ on Reaumur's scale. Observers, 



metres. Qf the ground. Of the air. 



It is evident, from this table, says our author, that under the 

 same parallel the temperature of the ground varies according 

 to the meridians, and that in order to have a just idea of the 

 progress of this temperature, we must compare places situated 

 under the same meridians. The above observations may 



• This is also the temperature of springs at the height of 1500 feet, so 

 that the low springs must have their origin at a great height. 



NEW SERIES. VOL. II. NO. II. APRIL 1830. R 



