Astronomy with an opera-glass: a popular introduction to the study of the starry heavens with the simplest of optical instruments, with maps and directions to facilitate the recognition of the constellations and the principal stars visible to the naked eye; (1888)
Serviss, Garrett Putman, 1851-1929 · New York, London, D. Appleton and company · leaf 156
small thepower of the in-strument used inviewing it may be.Strings of spots ofevery variety ofshape sometimesextend completely.across the disk.Our illustrationshows the appear-ance of the sun, asdrawn by the au-thor on the 1st ofSeptember, 1883.Every one of thespots and spot-groups there… … The Sun, September 1, 1883. 146 ASTRONOMY WITH AN OPERA-GLASS. cance and their true scale of magnitude. In glancing fromside to side of the suns disk, the eye ranges over a distanceof more than 860,000 miles—not a mere ideal distance, or anexpanse of empty space, but a distance filled by an…
Astronomy
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