1911 Encyclopædia Britannica/Schwabe, Samuel Heinrich

SCHWABE, SAMUEL HEINRICH (1789–1875), German astronomer, was born on the 25th of October 1789 at Dessau, where he died on the 11th of April 1875. At first an apothecary, he turned his attention to astronomy, and in 1826 commenced his observations on sun-spots. In 1843 he made the suggestion of a probable ten year period (i.e. that at every tenth year the number of spots reached a maximum), but it met with scant approval, and he continued his observations, which were afterwards utilized in 1851 by Humboldt in the third volume of his Kosmos. The periodicity of sun-spots is now fully recognized (see SUN); and to Schwabe is thus due the credit of one of the most important discoveries in astronomy. See H. H. Turner, Astronomical Discovery (1904).