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ON THE HYDROLOGY OF THE BASIN 



M E T E B L O G Y. 



'Die subject of meteorology has occupied the attention of the physicists of the United 

 States, and the results of observations, collected at a variety of points over almost the 

 whole of the continent, have led to valuable contributions to science in general. The 

 arrangements which were suggested by, and are under the control of, Dr. Henry, of the 

 Smithsonian Institution, at Washington, deserve especial mention ; as by means of these 

 exact predictions of coming storms have been made with actual certainty. And this is 

 one of the collateral advantages derived from the electric telegraph ramifying, to such a 

 prodigious extent, over the area of the United States and Canada. 



The number of stations at which observations are now constantly taken daily, by order 

 of the United States Government, under the direction of the United States Topographical 

 Engineers, is one hundred and fifty-seven. In addition to these, it is a requirement of 

 the regents of the public schools in the State of New York, as well as in most of the 

 other States, and in Canada, to keep a careful record of general meteorological observa- 

 tions. And in addition to the yearly results which are transmitted to central points (as, 

 for instance, in the case of the public schools of the United States to Albany), a large 

 number of these observations are also placed in daily communication, at a particular 

 hour, with the Smithsonian Institution, where the conductor in charge can see at a glance 

 all that is going on. And as the results of such an extensive system enables the philoso- 

 pher to test his generalizations, from hour to hour, we may expect very important 

 developments. 



All these observations seem to confirm the ideas promulgated by Dr. Henry (who sup- 

 poses) that the prevalent winds are the immediate effects of the great currents of the 

 ocean, modified by circumstances. It is supposed that the elevated temperature of the 

 water in the Gulf of Mexico, — which is greater than that of the water in almost any other 

 part of the globe, — is retained by the Gulf Stream until it reaches the shores of the polar 

 basin. The southwest winds, which accompany and blow from the Gulf Stream, share its 

 temperature ; and we feel the benefits on our English coasts and climate, which is far 

 more genial than would be due to our latitude. The southwest and westerly winds, which 

 prevail over the surface of the United States, serve to bear the heat of the Gulf Stream 

 from the American coast ; and when an easterly wind is produced by local causes, which 

 would bring the warm air of the Stream to these shores, it is cooled by crossing the polar 

 current flowing south, next the shore, which reduces its temperature to the dew point, and 

 produces the peculiar chilly effect familiar to the inhabitants of the Eastern States and 

 Canada ; while on the Pacific Coast, the west winds from the ocean cross the compara- 

 tively cool current from the north, and impart a uniform temperature to the western 



