22 Dr. Forry on the Climate of the United States, Sfc. 



With these preliminary remarks, we are prepared to enter into 

 a detail of the numerical results furnished in the several systems 

 of climate pertaining to the United States. The military posts 

 furnishing the thermometrical data will consequently be classi- 

 fied as under — 



General divisions of 

 the United States. Systems of climnte. 



( 1st Class. — Posts on the coast of New England, 

 I extending as far south as the har- 



1. Northern. 



bor of New York. 

 2d " Posts on the northern chain of lakes. 



3d " Posts remote from the ocean and in- 



land seas. 



r 1st Class. — Atlantic coast from Delaware Bay to 

 2. Middle. < Savannah. 



( 2d " Interior stations. 



o Q .1 ( 1st Class. — Posts on the Lower Mississippi. 



6. tooutiiern. ^ ^d " Posts in the Peninsula of East Florida. 



These general divisions, intended as well to facilitate descrip- 

 tion as to express the operation of general laws, may be regarded, 

 in a great measure, as arbitrary. The northern embraces a re- 

 gion characterized by the predominance of a low temperature ; 

 in the southern, a high temperature prevails ; while the middle 

 exhibits phenomena vibrating to both extremes. Each of these 

 general divisions, as exhibited in the table above, is subdivided 

 into well marked classes or systems. 



As the present paper will not allow the admission of extensive 

 tables of figures, the writer is obliged to confine himself to mere 

 results, referring the reader who may be more curious on this 

 subject to the author's work, " The Climate of the United States 

 and its Endemic Influences," which contains a series of exten- 

 sive tabular abstracts of instrumental observations. These re- 

 sults are obtained from observations made at the various military 

 posts between 24° 33' and 46^ 39' of north latitude, embracing 

 a space of 22° 6', and an extent of longitude stretching from 

 the Atlantic to the Pacific. The thermometrical observations 

 were made thrice daily ; and as the mean of each month is cal- 

 culated from 90, and of each year from 1,095 observations, the 

 numerical ratios, it is believed, will give an approximation to the 

 truth as near as can be realized by ordinary observation, and a 

 mean sufficiently correct for every contemplated purpose. The 

 results, at the majority of the posts, are based on from five to ten 

 thousand observations. 



