fome T bermomefncal Experiments . 521 
feftly dean as poffible, which is a neceflary precaution in this 
experiment, which depends upon a very great accuracy of 
weight. Then I introduced fome mercury into the ffern of 
this thermometer, taking care that none of it entered the ball, 
and, by adapting a fcaie of inches to the tube, obferved that 
4,3 inches length of the tube was filled with the mercury. The 
thermometer was now weighed again, and from this weight, 
the weight of the glafs found before being fubtra&ed, the re- 
mainder, viz. 0,24 gr. (hewed the weight of fo much quick- 
filver as filled 4,3 inches of the tube. Now the ball of the 
thermometer, and alfo part of the tube, were intirely filled 
with quickfilver : then, in order to find out the weight of the 
mercury contained in it, the thermometer was weighed for the 
laid time, and from this weight the weight of the glafs being 
fubtra&ed, the remainder, viz , 3205 grs. (hewed the weight 
of the whole quantity of quickfilver contained in the ther- 
mometer. 
By companion with a graduated thermometer in hot and cold 
water, I made a fcaie to the new thermometer according to 
Fahrenheit’s, and by applying a fcaie of inches found, that 
the length of 20° in this (bale was equal to.. 1,33 inch. But 
0,24 gr. was the weight of fo much mercury as filled 4,3 
inches length of the tube ; therefore, by the rule of propor- 
tion it will be found, that the weight of fo much quickfilver as 
fills 1,33 inch of the tube, viz. the length of 20° is equal to 
0,0742 gr. nearly, and that the weight of fo much quickfilyer 
as fills the length of the tube that is equivalent to one degree, 
is equal to 0,00371 or. Now it is clear, that the weight of the 
whole quantity of quickfilver contained in the thermometer is 
ito the weight of fo much quickfilver as fills the length of one 
degree in the tube, as the bulk of the whole quantity of quick- 
Y y v 2 filver 
