98 



THOUGHTS ON THE INFLUENCE OF ET1IEK 



Indian summer, popular observation has supplied us with data which the notes of astrono- 

 mers have failed to furnish. 



There arc some parts of the world where the force of special causes is such as to pre- 

 vent the Indian summer from being felt. In the British islands the climate is, in a great 

 measure, determined by the influence of the Gulf Stream. On the coast of California, the 

 Indian summer is not known, probably from the existence of the Ku.ro Siwo* or Japan 

 Stream, a current in the Pacific Ocean, having geographical analogies with the Gulf Stream. 



In the polar regions of the earth, the influence of the sun's rays in producing heat, is at 

 its minimum, while any effect derived from the medium by which our planet is surrounded, 

 is, except in special cases, equally displayed in all parts of the earth. 



Any depression in temperature, owing to ethereal influence, must be most perceptible 

 in the polar regions, because there the other cause of heat is at its minimum. 



In the month of March our planet attains its extreme distance from the ascending cur- 

 rent, we should, therefore, look for the greatest degree of cold in the polar regions in that 

 month. 



Dr. E. K. Kane, during the winters of 1853-4 and 1854-5, spent in lat. 78° 37', on 

 board the brig Advance, found the coldest weather in the month of March.f 



Dr. I. I. Hayes, who was surgeon to the expedition under Dr. Kane, confirms his report 

 of the temperature of the weather in March. 



Dr. Hayes also passed the winter of 18G0-61 on board the schooner United States in 

 lat. 78° 17'. The coldest weather of that year occurred in the month of March. J 



According to this observer, such is the uniform experience of Arctic navigators. 



Even in the temperate regions of the earth, the month of March is a most boisterous 

 season. One of its peculiar features is a chilling atmosphere, accompanied by considerable 

 power in the sun's rays. It is said to "come in like a lion, and go out like a lamb;" an 

 order of events to which not only the obliquity of the ecliptic, but also the relation of the 

 sun's equator to the earth's orbit, eminently conduces. 



At the opposite season of the year, in the month of September, the; earth reaches its 

 extreme distance from the ethereal current, for that half of the year. 



From the relation of the ethereal current to the solar equator, the earth does not' then 

 attain the same distance from the heated mass as in the month of March. We cannot 

 expect, therefore, to find the same degree of cold exhibited in September as in March. 

 And such is common experience. 



* See "A paper on the Kuro Siwo, or Japan Stream." Read before the American Geographical and Statistical 

 Society by Silas Bent, Lieutenant U. S. Navy. New York, January 24th, 1850. 

 f In a private conversation. 

 | In a narrative delivered to the Academy of Natural Sciences, Philadelphia, November 26th, 1861. 



