RESULTS OF METEOKOLOGICAL OBSERVATIONS. 229 



begins not far from the Mississippi river ; and yet in others, on the meridian 

 of Lake Michigan or of Lake Erie. In well-known instances a northeast 

 storm extends from the Atlantic only to the summit of the Allegany range 

 of mountains, where it meets with the western general current strong enough 

 to arrest its progress, and eveu to force the storm back to the Atlantic. 



These storms often extend along the eastern coast of the United States 

 to Nova-Scotia ; being more pevere at the north or south, as the causes of 

 change are more active and powerful. The equinoctial storm of September 

 23, 1815, was far more severe on the coast of New-England than south of 

 New- York ; and the greatest damage was done to buildings, trees, and to 

 vessels in ports, by the northeast wind, before the change from the north- 

 west occurred. The violence of this particular northeast wind, even in the 

 western part of Massachusetts 140 miles from the ocean on the east, is yet 

 well remembered. It was shown too by another fact : the salt water of the 

 ocean was blown inland forty miles in sufficient quantity to kill the foliage 

 of trees, which, a few days after the storm, presented the appearance of 

 scorched leaves. 



Sometimes the northeast storm extends westward only to the summit of 

 the Green mountains, or that part of the range lying in Massachusetts im- 

 mediately west of the Connecticut river. On this range the northeast wind 

 and rain meet the wind from the west bearing clouds to the summit of the 

 range, but yielding no rain to Berkshire county or its western or even its 

 middle portion. On the eastern side, on these occasions, a great deal of rain 

 falls ; and in one such case on record, immense damage was done along the 

 streams emptying eastwardly into the Connecticut river. The general west 

 wind here supplied a part of the rain along the mountains ; the opposing 

 currents mingling their vapor, and thereby producing a greater effect. This 

 example shows the great power of the west wind in limiting the extent of a 

 storm from the east, involving a great difference in the quantity of the 

 materials acted upon. If it is urged that such a storm is only the ending of 

 a more extensive one chiefly expending itself over the Atlantic ; even if this 

 were admitted, it would be true that the storm would pass further west, 

 were not the general current from the west the prevailing power. 



Another fact demands attention, viz. that a northeast storm begins earlier 

 at the south than further north. Franklin long ago asserted that storms 

 began three hours earlier at Philadelphia than at Boston. The general fact 

 has been so often observed in the last fifty years, that it cannot be doubted ; 

 but the time may vary from three hours, according as the violence is greater 

 or less. The fact itself results from the direction of the eastern coast, and 

 the several obvious differences between the land and ocean winds at the 

 south and at the northern part of the United States. 



Thus the direction of the coast is very nearly parallel to a line drawn 

 from Cape Sable at the southern extremity of Florida, to Cape Race on the 

 southeast point of Newfoundland ; or, better still, a line from the east coast 

 of Florida, Lat. 30° N. and Lon. 80° W., to the north point of Newfound- 

 land, Lat. 51J° N. and Lon. 54° W., a course but little east of sonthwest. 



