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see that in their climate the Atlantic States are different from all these. A 

 medium atmoi^phcre, both in its heat and moisture, is the most favorable for the 

 production of cotton, tobacco, and wool. And such is that of the Atlantic States. 

 What is the cause of the difference in the climates of these States and that of 

 California and the countries just named? The answer is interesting to all, but 

 more particularly to those who wish to see clearly the futui-e of our cotton, 

 tobacco, and wool production. The answer requires some consideration of the 

 machinery used in nature to distribute moisture, and we now place it before 

 our readers in such way, that, aided by plates, we hope to convey to them 

 clear perceptions of its character. 



Let us suppose the sun to be directly above the equator, as it is on the 22d 

 days of March and September. There is then this condition of the atmosphere over 

 the world. Nearly under the sun is a belt of calm air, about five hundred miles 

 in Avidth, extending around the earth. On each side of it is a belt of dry air, also 

 encircling the earth; the one north of the equator is about fourteen hundred 

 miles wide, and that south of it from sixteen hundred to two thousand miles in 

 width. The air in the first of these blows steadily and gently from the northeast 

 towards the equator, and the air in the second from the southeast to the equator. 

 North and south of the belts of dry winds, and extending to the poles, there 

 prevail variable winds and showers. 



The belt immediately under the sun gives heavy rains, and is called the Belt 

 of Calms, or ihe Uainy Belt. We shall refer to it by the latter name. The dry 

 belts on either side of it are known as the Trade Winds. It was these which 

 wafted Columbus to the American continent. The atmosphere beyond these 

 and extending to the poles is called the Variable or Extra-tropical belts. 



This machinery moves with the sun, and when it has reached its furthest 

 northern point, the tropic of Cancer, at about 23.^ degrees of north latitude, and 

 on the 21st day of June, the rainy belt is nearly at that point, and the northern 

 limit of the trade-winds is at the 39th degree of latitude — that is, the latitude of 

 W^ashington, Cincinnati, Alton, and Independence, and within three degrees of 

 the northern boundary line of California. The following climatic map exhibits 

 the geographical position of these respective belts on the 21st day of June. 



