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vertical just north of the northern part of Chile, in South America. 

 These belts, moving south with the sun during six months, the region 

 of conflict between the polar winds and the variable winds which in 

 summer were over British Columbia. Washington Territory, and 

 Oregon, have now moved south over Oregon and the northern and 

 middle parts of California. The temperature of the earth's surface 

 and the air in contact with it, have been lowered by the withdrawal 

 of the sun's more direct rays, and the polar winds are permitted to 

 reach farther to the south without increasing their temperature. The 

 region of calms and the southern limit of the variable winds have, 

 of course, also moved south with the sun beyond the tropic of Can- 

 cer. At this season, in the Pacific, the trade wind is not usually 

 found north of latitude thirteen degrees. When, in winter, the 

 descending return trade wind, coming from the southwest, meets the 

 coast south of Cape St. Lucas, it is forced by the Cordilleras and the 

 configuration of the main coast into the Gulf of California, and is 

 deflected into a course from the southeast, or to be more exact, as 

 shown by the records kept by Dr. Gibbons, into a course from the 

 south-southeast. Without doubt, the southwest return trade wind 

 which strikes the coast of Lower California in winter, north of Cape 

 St. Lucas, is deflected by the high mountains parallel to the shore, 

 and also passes over our coast counties as a southeast wind. H. S. 

 Warner, in a paper read before the American Association for the 

 Advancement of Science at its Baltimore meeting, in eighteen hun- 

 dred and fiftv-eight, was the first to note the fact that the waters of 

 the Gulf of California supply the moisture to the southeast wind 

 that bears to us our rains. It may be objected that the Gulf of Cali- 

 fornia has not sufficient area from whence could be delivered the 

 great volume of southeast winds that at times, daring our winters, 

 flow over this State. The gulf is not the cause of this wind, but it is 

 the channel through which it flows, and gives to it direction. AVhen 

 the sun is vertical on the coast of Bolivia, just north of Chile — at 

 our midwinter — he has carried south with him the northeast trade 

 winds, until, as has been stated, they do not prevail north of about 

 latitude thirteen degrees. The region of calms, where the great body 

 of the upper current returns to the earth again to join the trade winds, 

 is, at this season, between latitudes thirteen and eighteen degrees. 

 North of this region of calms, at this time, those portions of the 

 upper current which pass further north, descend to the earth, under 

 Professor Henry's law, as southwest winds. At latitude twenty 

 degrees the west coast of Mexico projects a bold headland into the 

 Pacific Ocean, known as Cape Corrientes. South of the cape the 

 trend of the coast for nearly two thousand miles is east-southeast ; 

 north of this cape, the trend for more than one hundred miles, to 

 Mazatlan, is north; from Matzalan to the head of the Gulf of Cali- 

 fornia, a further distance of six hundred miles, it is north-northwest. 

 The Sonora arm of the Cordilleras rises above the table land of Mexico 

 at latitude twenty degrees, and runs north-northwest along the coast. 

 nearly to the head of the Gulf of California. All of these southwest 

 winds that strike the coast from Cape Corrientes north to Cape St. 

 Lucas are deflected by these mountains, and forced up the gulf as 

 south-southeast winds. The United States Coast Survey have lately 

 completed the survey of this gulf and parts of the Mexican coast 

 north of Cape Corrientes. When their record of observations of the 

 course of the prevailing winds in winter, the barometric pressure and 



