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current of water, and wafted in clouds over the land, 

 varying on its course, until meeting with some obstruc- 

 tions by which its current is slackened, it immediately 

 deposited its alluvion, (for it is nearly the same thing) 

 to the leeward of whatever object may interrupt its 

 course. Jt may be said, who does not know all this? 



But there is a variety of other phenomena of a simi- 

 lar nature accompanying he operations of winds, one 

 of which is particularly worthy of notice in the present 

 instance. 



It is, that when a river running through a country is 

 confined for any considerable distance from its influx 

 into the sea or bay, between high ridges of hills, or 

 banks, there is a current of wind rushing down its 

 course, differing one or two points from the general 

 course of the wind that may be prevailing at the time, 

 or blowing in nearly a corresponding direction. 



Thus if a river runs in a southerly direction, and the 

 wind is blowing fresh from the north east, and raising 

 the dust and sand in its course, when it meets with the 

 current of air flowing down the river, under the circum- 

 stances which I have mentioned, the same phenomena 

 may be observed, as when the rapid currents of two 

 rivers unite ; the sand and dust are whirled around in 

 the most confused manner, and at last let fall upon the 

 shore, and in the water, where, if the tide is setting 

 towards the shore, the sand will be again thrown upon 

 the beach. Hence it is, that we often see narrow pro- 

 jecting points of sand at the mouths of rivers running 

 through a sandy country. They may be observed at 



