A TOTAL ECLIPSE OF THE SUN

Abstract

special class of objects within our system the comets. It has seemed to me appropriate that our third lecture should be devoted to the Sun itself, the most important object in the universe for us the source of heat, light, mechanical and electrical power, and, in the material sense, of life itself, on our little globe. But the phenomena of the Sun as revealed by our modern studies are so multifarious and raise so many intricate and interesting problems that it is quite impossible to treat them all in a single lecture. It is necessary to select, and I have chosen to place the emphasis in what I shall say this evening upon those phenomena which are more or less directly associated with a total eclipse of the Sun. There are special reasons for this choice : No other natural phenomenon is so impressive, so startling, so fascinating, as a total eclipse of the Sun ; many important advances in our knowledge of the Sun have had their origin in eclipse observations; the present year is a year of eclipses seven, the maximum possible number, occurring within it; a total eclipse of the Sun will be visible in the western part of this country next year June 8, 1918 for the first time in twenty-nine years; and, finally a point of particular interest to us who are gathered here our Society, the Astronomical Society of the Pacific, may be said to owe its existence to a total eclipse of the Sun. This was the eclipse of January 1, 1889, which, beginning at sunrise in the North Pacific Ocean, entered California near Point Arena at about 1 :45 p. m., and swept across the State northeastwardly in a path some eighty miles broad, to end at sunset in northeastern Canada.