EXPLANATIONS AND REMARKS 



CONSOLIDATED TABLES OF RESULTING MEAN TEMPERATURES FOR EACH 

 MONTH, SEASON, AND THE YEAR. 



That part of the tables which refers to the United States is arranged in alpha- 

 betical order according to states and territories, and the names in each subdivision 

 are given alphabetically. For all stations beyond the limits of the United States it 

 was considered more advantageous to adopt a geographical arrangement, but the 

 alphabetical sequence of stations imder each geographical district is preserved. 



The tables contain: The number and name of each station, its latitude and 

 longitude, its elevation above the sea when known, its mean temperatures for 

 each month, each season, and for the whole year, the beginning and ending of the 

 series of observations, its actual extent, the observing hours, the name of the ob- 

 server with references. 



The geographical positions are given to the nearest minute of arc, as far as known, 

 the longitudes are counted as usual west of Greenwich. The positions which 

 became known through the operations of the United States Coast Survey are 

 reliable, as well as those given upon the authorities of the United States Lake 

 Survey, officers of the United States Army, directors of astronomical observatories, 

 and, in general, all those positions which have been determined by direct astro- 

 nomical observations and those connected with the General Land Office. Positions 

 given on the authority of the observer, and these are by far the most numerous, 

 are less trustworthy, since most of these were taken from State or county maps 

 having no adequate astronomical basis. The results for longitude depending on 

 the electric telegraph are of so recent date that but few maps have as yet incor- 

 porated them. Although no pains have been spared to render these geographical 

 positions as trustworthy as possible, they are, in general, when taken from maps 

 evidently in the given latitudes affected with a probable uncertainty of from 

 J:; 3' to J;2 5' and in the given longitudes with a probable uncertainty of from ^ 5' 

 to ± 8'. Fortunately for the immediate wants of the discussion of temperatiire a 

 moderate approximation to the true position suffices. The elevations of the 

 observing stations depend in all cases upon the statements of observers; these 

 also no doubt require considerable improvement, as but few depend upon direct 

 hypsometric measures or on measured differences of level from known railroad or 



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