Stars and telescopes; a hand-book of popular astronomy founded on the 9th ed. of Lynn's Celestial motions (1901)
Todd, David P. (David Peck), 1855-1939, Lynn, William Thynne, 1835-1911 · Boston, Little, Brown · leaf 406
HALES TYPE OF SPECTRO-HELIOGRAPH (Constructed by BrasHHAR) Telescopes and Houses for Them 353 and separating the flint three inches from it, the com-bination becomes an objective perfectly corrected forthe actinic rays — or nearly so. The fact, however,seems to be that there is a trifling sacrifice… … UNIVERSAL SPECTROSCOPE BY PRASHEAR (Arranged for visual work. Light enters the spectroscope at the extremeleft, passes through the prisms or is reflected from the grating in theflat-topped box at the right, and comes to the eye which is placed at theeyepiece on the micrometer in the 7iiiddle of the…
Astronomy
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