on some of the leading doctrines of caloric , &c. fSg 
discordances which no ingenuity can harmonize. At that 
time, 225 0 of Fahr. = 222 0 of the new scale, gave a force of 
vapour equal to 38.3 ; it is now 39.5 . 252°.6 F. = 242 0 D. 
then coincided with an elasticity of 58.6 inches ; above, it is 
69. And finally, 28 i°. 2 F. = 262° D. were opposite to 90 
inches; they have become here 120. And yet no new ex- 
periments on the vapour of water have been adduced, to 
justify such immense alterations. 
It may be said, indeed, that these changes arise merely 
from the substitution of one hypothesis for another ; but the 
deviations from experiment are even more remarkable, since 
as 282° new scale, correspond to 3ii°.3 Fahr., the difference 
amounts to 43 inches, being more than one fourth of the total 
elastic force generated at that high temperature. 
When we turn our attention to ether, we find the discre- 
pancies, if possible, less easy to reconcile. At the temperature 
of 212 0 , for example, where the old and new scales meet for 
the last time, the force of its vapour by the geometrical 
progression exceeds that found from experiment, by the 
enormous quantity of 6y inches and a half ; amounting to two 
fifths of the whole elastic force evolved. 
May we venture, then, to conclude, from these multiplied 
comparisons, that the progressions of elasticity in vapours, 
taught by Mr. Dalton, are geometrical fictions, intended to 
quadrate with his notions concerning temperature ; but not 
consonant with the laws or phenomena of nature ? 
Within a moderate compass, indeed, it is not difficult to 
suit the ratio of elastic force and the thermometric graduation 
to each other ; but the prosecution of the enquiry into ranges 
more remote, detects the fallacy of such hypothetical adapta- 
