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Signal Corp. Telescopes; and Military Optics ATS member Peter Abrahams writes: "Antique telescopes were sold in large quantities to sailors, astronomers, voyeurs, and the military, but survive in relatively few numbers because their glass lenses and brass tubes were easily damaged. Telescopes used for astronomy give an inverted image, but many old telescopes were used for marine & military purposes and have more complicated optics that show the world right-side up. Spyglasses are smaller, hand held telescopes that collapse into their tube and focus by drawing out the tube to the correct length. A more compact instrument, with three or four sections, is also more delicate, and sailors usually preferred a single draw spyglass. They are almost always of brass, occasionally of nickel silver or silver plate; and usually covered with leather, or sometimes wood veneer. Solid wood barrel spyglasses (with a brass draw tube) tend to be early and rare." "Before the middle of the 1800s, makers put their names in elaborate script on the smallest draw tube, but as 1900 approached, most switched to plain block printing. British instruments from World War One are commonly found by a variety of makers but sharing a format of a 2" objective, 30" long with three draws extended, tapered main tube, and sometimes with low and high power oculars and a beautiful leather case. U.S. Navy WWII spyglasses are quite common but have good optics, and focus by twisting the eyepiece, which makes them weather-proof. Very massive, short, brass telescopes are usually gun sights or ship equipment and have little interest to most collectors. Modern spotting scopes often use a prism to erect the image, and are of great interest if made by the best makers, including Nikon and Zeiss. Several modern makers still use lacquered brass, and many replica instruments have been produced, and are frequently seen being offered in the internet auctions. A telescope with no maker's name is much less interesting than a signed instrument, and "Made in France" is the most common mark on old brass spyglasses. Dollond of London made instruments for 200 years and is probably the most common name on antiques, but because of their important technical innovations and very high quality, Dollond telescopes are always valuable." "Spyglasses are delicate instruments that were subject to severe use under all weather conditions. Cracked or deeply scratched optics are impossible to repair and lower the value considerably. Most lenses are doublets, two lenses glued together, and deteriorated cement is common. This looks like crazed glaze and is fairly difficult to repair. Dents in the tube and damaged or missing leather covering can usually be fixed. The best test of a telescope is to use it, and the image should be sharp and clear." Reference and Research Sources: Cheetham, J., "Old Telescopes by Reginald" can be secured from: Publisher SAMEDIE, c/o Lister Art Books (Distributer), PO Box 31 Southport, Lancashire, PR9 8BF. Cost: approx. 15. [see brief review below] A new booklet is currently out and available titled: "Old Telescopes". It is only 66 pages in length and focuses on draw telescopes. The booklet is written in layman's terms but is quite informative in a number of areas. For example, it provides information on: "the design and construction of old telescopes to serve as a guide identifying and dating the various types that are generally found in collections and antique trade today." Also, advice on restoration and conservation is given as well. (Source review courtesy of ATS Member Robert Ariail) Clifton, Gloria "Directory of British Scientific Instrument Makers, 1550-1851" (Zwemmer, London, 1995) Clarke [T.N. Clarke, A.D. Morrison-Low, and A.D.C. Simpson, "Brass and Glass" It was published by the National Museums of Scotland in 1989. Turner, Gerard L'E. "Antique Scientific Instruments" Wynter, Harriet "Scientific Instruments" King, Henry C. "The History of the Telescope" Dover Taylor, E.G.R.
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