The solar activity 1833-1900

Abstract

A close examination of the curves representing the varying amount of spotted area on the Sun’s surface, shows that no two successive cycles are alike either in form or area. The individuality of the cycles seems, on further inspection, to be repeated after a certain period of time, and this peculiarity, coupled with a like variation in the curves representing the variations of the magnetic elements, and with suspected cycles of change in various terrestrial phenomena, suggested a new investigation of the whole subject. The object of this communication is to place before the Royal Society the first results which an examination of the various records has furnished.