Note 296 — Chapter XIII · THE SOLAR CYCLE.
Reading edition
Clerke, Hist. of Astr. pp. 148, 149, 4th ed.; Spoerer, Potsdam Publ. Bd. x. part i. 1894.
Reading edition
Clerke, Hist. of Astr. pp. 148, 149, 4th ed.; Spoerer, Potsdam Publ. Bd. x. part i. 1894.