Appleton's dictionary of machines, mechanics, engine-work, and engineering (1869)
New York, Appleton · leaf 715
Hcrschelian telescope.—This construction differs from the others in having no second mirror. Thelarge speculum A B, Fig. 3408; is placed at the bottom of the tube in an inclined position, so as to bringthe focal image a near the edge of the tube, where it is viewed directly by the eye-piece F…
Mechanical engineering
Internet Archive · Gerstein Library, University of Toronto · Public Domain Mark 1.0. Free to use for anything.
