22 EXPERIMENTS ON 



The thermometer, at the beginning of this opera- 

 tion, was KT'-, and at the end 1^\ 



From the above experiments, it will appear, that, 

 ifince by the application of extreme heat (procuring 

 extreme dryness) the index had revolved from right 



R 



to left, 2+105" 



and, by the application of extreme moisture, 



from left to right, ^^9.<^5 



it follows, that the sum of these two quan- 

 tities, viz. =9+ 40 

 is the compass of the stem. 



Tliis result evinces, that the mean state of the at- 

 mosphere does not correspond, nor can it on any oc- 

 tasion, with the mean of the power of this instru- 

 ment *. 



A second stem having been selected, and the same 

 process, as above related, repeated ; it moved by ex- 



treme heat 2+290'', and, by extreme moisture, 



8 + 320°; so that the compass of this fibre was 



11+250*; which exceeded that of the former by 



2+210; but, on examining it closer, after the opera- 

 tion, it was found that, although taken of the same 

 length, it contained one twist more than the former j 

 which accounts for its greater compass, 



EXPERIMENT VI. 



Application of Steam. 



Three stems having been selected, and being fixed 

 as usual, the steam of boiling water, issuing from 



* Tlie stem, which was used for this experimenl, was afterwards 

 compared, when made up, with other hygrometers ; and it did not 

 appear to have lost of its activity, by this process. 



