WAS LEWIS EVANS OR BENJAMIN FRANKLIN THE 



FIRST TO RECOGNIZE THAT OUR NORTHEAST 



STORMS COME FROM THE SOUTHWEST? 



By WILLIAM MORRIS DAVIS. 

 (Read April 20, 1906.) 



The account of the " Middle British Colonies in America," 

 prepared by Lewis Evans and published in Philadelphia in 1747, 

 contains a remarkably clear and appreciative description of the 

 main features of New Jersey and Pennsylvania. It is illustrated by 

 a map which, like the text, bears witness to an extraordinary acute- 

 ness of observation and as well to an unusual power of general- 

 ization on the part of the author, who must be ranked as an early 

 leader among American geographers. The map contains a number 

 of explanatory legends, inserted where topographical details were 

 wanting ; and here we find, among various items, a significant state- 

 ment regarding the movement of storms : " All our great storms 

 begin to leeward ; thus a NE storm shall be a day sooner in Virginia 

 than in Boston." This brief statement has been taken to be the 

 first recognition, as it surely seems to be the first published announce- 

 ment of the progressive movement of storms, on which so much of 

 the modern art of weather prediction depends. The statement is 

 however not easily accessible to citation, for apart from the great 

 rarity of complete copies of the first edition of Evans' essay — the 

 map being lost from some of the few copies known to me — the 

 map in the second edition was amended by replacing some of the 

 legends with newly gathered topographical data ; and among the 

 matter thus removed was the statement above quoted concerning the 

 movement of storms. 



Evans' publishers were Franklin and Hall, and there is good 

 reason to believe, as has already been pointed out by students of 

 this question, that it was Franklin and not Evans who provided the 

 statement concerning storms, along with some account of lightning 

 and electricity, subjects with which Evans was not particularly 



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