180 



WRITINGS OF JOSEPH HENRY. 



[1855- 



Professor Caswell, of Brown University. This gentleman 

 has made a series of observations extending through upward 

 of a quarter of a century, and has presented the whole to the 

 Smithsonian Institution for publication. 



Temperature of Providence, Rhode Island ; by Prof. A. Caswell. 



It appears from this table that the coldest month is Janu- 

 ary, and the warmest are July and August, which are nearly 

 the same. The mean temperatures of April and October are 

 nearest to the mean of the year. In the two periods of ten 

 years each, at Providence, the difference between the mean 

 temperatures is but two-tenths of a degree ; the differences 

 also between the mean temperatures of the several months 



