STATE HORTICULTURAL SOCIETY, 



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low, barometers become storm centers which traverse the surface of the earth 

 in an easterly direction. The temporary high barometers, if free, in North 

 America, take a southeast course and join the permanent high barometer be- 

 tween the Bahama and Bermuda islands. Galton very appropriately named 

 the winds blowing out from under an area of high barometer anti-cyclonal ; 

 since as they diverge from a common center on all sides in curves, they 

 never can produce cyclones. He has appropriately called those blowing 

 into an area of low pressure cylonal, since converging to a common center 

 they must inevitably produce cyclones, of more or less energy. 



We have said that both the out-blowing and in-blowing winds have a 

 curvilinear motion. Therefore, in order to know and to explain the 

 direction of the wind, under given conditions of pressure, we must know 

 the direction of these curves. Take any two points, A and B, for in- 

 stance. From the point A as a center draw curves from the center out- 

 wards to the right, thus -K \ and from B as a center draw curves to the 

 left outwards, thus cB*. Then A will represent the direction of both 

 cyclonal and anti-cyclonal winds in the Northern Hemisphere ; and B 

 those of the Southern Hemisphere. It will be perceived that the direc- 

 tion of the anti-cyclonal winds in the Northern Hemisphere is direct, 

 that is, they have the same direction as the hands of a watch, and the cy- 

 clonal ones retrograde, that is, contrary to the hands of a watch ; and 

 that in the Southern Hemisphere these movements are reversed. 



Now let the line E.W. represent 

 the equator between South America 

 and Africa, and the oblong ellipse A 

 the area covered by the permanent 

 high barometer in the Atlantic, 

 north of the equator ; and the el- 

 lipse B the permanent high barome- 

 ter in the Atlantic, south of the 

 equator; then the arrows on the 

 nearer sides show the direction the 

 wind blows into the permanent low 

 barometer along the equator E. W. 

 The wind on the north side is seen 

 to be from the northeast, and that 

 on the south side from the southeast ; 

 in other words, you have before you 

 the laws and causes of the northeast 

 and southeast Trade Winds. 



Take another illustration. I have 

 already stated that in the summer, 

 that is, from the time the sun crosses 

 the equator, in his northern journey, 

 until he again retires beyond it, there 

 is a periodical low barometer in Cen- 

 tral Asia; while at the same time, it 

 l)eing winter in the Southern Hemis- 

 phere, there is a high barometer in 



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