RECAPITULATION.

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meter in winter are generally greater in the eastern thanin the western parts of the United States.” This also explainswhy less rain and snow fall in the north-western territories inwinter, a circumstance to which the prairies, or treeless regions,probably owe their origin. But why southerly winds blowlonger on the Atlantic coast than in the western territories isa phenomenon which I am not prepared to explain.

In the United States, then, the winds may all be regardedas modifications of the south and of the west wind. The modi-fications of the south are the north-east, east, south-east,and south-west, which, after blowing for some time, arecharacterised by a rising temperature and a falling barometer.The modifications of the west wind are the north-west andnorth, which are characterised by a low temperature and highbarometer.

Indeed, the difference of temperature betwixt the coldArctic current which flows down Baffin’s Bay and along theLabrador coast, and the Gulf Stream as they meet off thecoast of Newfoundland, is not nearly so great as the differenceof temperature betwixt the west winds of the UnitedStates and the south from the Gulf of Mexico. It is some-what curious that, while the aqueous current or Gulf Streamhas been so ably investigated, the aerial current, which hasproduced so grand a result, has been comparatively overlooked ;at least, the connection between the tropical winds of theCaribbean Sea, and the south winds of the United States, hasreceived little attention since Volney wrote.

Recapitu latio n.

The calms of Cancer, with belt of high barometer andrainless regions, under the 30th latitude, do not exist in theproximity of the American continent.

The rainy and stormy character of the Gulf of Mexicoand Southern States of America, is owing to the abnormalcourse of the tropical winds in those regions.

The southerly winds of the United States are more pre-valent during Bummer, as the heated continent draws the air