Double Refracting Telescope

| View Cart ⇗ | Info

“The inversion of the object is of little consequence when the instrument is employed for astronomical purposes, for since the forms of the heavenly bodies are spherical, their positions, in this respect, do not affect their general appearance. But for terrestrial purposes, this is manifestly a great defect, and therefore those constructed for such purposes, as ship, or spyglasses, have two additional lenses, by means of which, the images are made to appear in the same position as the objects. These are called double telescopes.” -Comstock 1850


J. L. Comstock A System of Natural Philosophy: Principles of Mechanics (: Pratt, Woodford, and Company, 1850) 254


TIFF (full resolution)

2400×664, 212.2 KiB

Large GIF

1024×283, 35.8 KiB

Medium GIF

640×177, 19.2 KiB

Small GIF

320×88, 7.1 KiB