4 54 ? Appendix to Dr. Blagden's Report 
heated up to ioo°, when the mixture in the two tubes was 
found to have risen to 187 above o. I again cooled it down 
to 30°, and found it to stand in the two tubes at 122 b flow o. 
Lastly, I heated it again up to 6o°, and found it to stand in the 
two tubes at no more than 4 above o. 
From the above experiments it appears, that the contraction 
of the mixture in cooling down from 6o° to 30°, is 120 -{- 5,5 
= 123,5; and the total expansion on heating up from 30° to 
ioo°, including the error arising from cooling it down from 
6o° to 30°, will be 120 -j- 187 = 307; but in cooling down 
again from ioo° to 30°, we shall have for the contraction 
187 + 122=309. The former quantity of 307 errs from 
the experiments by weight 3,57, and the latter 1,57 division, 
in defect. 
But by taking a mean of the quantities found on heating 
the mixture up from 30° to ioo°, including the error arising 
from some of the fluid being left adhering to the tube, in 
cooling down from 6o° to 30° previous to its being heated up 
from 30° to ioo°, we shall have for the total expansion 307,25, 
and it was found in cooling down from ioo° to 30° to be 309 ; 
the difference is 1,75 ; if then we say, as 182 : 1,75 : : 125,5 
: 1,21, the last number being subtracted from 307,25, we shall 
have for the true expansion in heating up from 30° to ioo°, 
306,04 ; differing from the experiments by weight 4,53 divi- 
sions, in defect. 
From what was advanced by Mr. Ramsden respecting the 
accuracy of the two instruments with which the foregoing 
experiments have been made, there was great reason to ex- 
pect that different results would have been found. It appears 
that no dependance ought to be placed on experiments made 
