142 Dr. Hare on the Cause of Heat. 
the month of July. I believe I am authorsed in the con- 
clusion therefore, that the whole quantity which fell in this 
town, during that month, exceeded twenty-four inches on a 
level. 
I have not the means of determining whether similar rains 
have, or have not, occurred in other noite It is stated 
in the Christian Observer, that the mean annual quantity of 
rain is at Rome thirty-nine inches; in England thirty-two ; 
and at Petersburgh sixteen. It is also stated in the same 
work, (Vol. 8th, page 733,) that ‘* the quantity of rain which 
fell in September (1818) was equal to four inches in depth, 
a quantity, perhaps, unprecedented at the like season, in 
the metrorological annals of this country, (England.) The 
depth of rain in the two preceding months was likewise unu- 
sually great, having exceeded seven inches.” In many 
tropical regions the mean annual quantity greatly exceeds 
that, which exists in the countries above mentioned. 
Art. XII.—Letter from Ropert Hare, M. D. Professor 
of Chemistry in the University of Pennsylvama, &c. 
&c. to the Editor, in opposition to the conjecture that heat 
may be motion ; and in favour of the existence of a ma- 
terval cause of calorific repulsion. 
Dear Sir, 
In two memoirs published in your Journal, I have en- 
deavored to shew that caloric and electricity, are collateral 
agents in galvanism, the ratio of the former to the latter, in 
quantity, being as the extent of the operating superficies to 
the number of pairs into which it may be divided. In those 
publications I assumed, that the causes of heat and elec- 
tricity are material fluids. Although this view of the ori- 
gin of calorific repulsion is taken by a great majority of 
chemists, it has been combated, both by Rumford, and 
Davy: the former famous for his ingenious, instructive and 
laborious experiments ; and the latter distinguished by the 
most splendid discoveries. With the utmost deference for 
the authority of these great men, especially the latter, I send 
the following remarks made in answer to his hypothetical 
