Naval Telescopes

Though telescopes have a long history they were only produced in quantities to be widely available in the late 18th century.

Problems of lens polishing, lens composition, and manufacturing were slowly overcome and the telescope became a vital element of seafaring equipment. Superior optics meant that navigation hazards could be identified at longer distance, and in time of war and piracy it meant that approaching vessels could be recognized at longer distances. It also made the use of communications by signal flags practical.

Early telescope construction consisted of barrels constructed of leather, vellum, or wood with the lenses held in place by brass fittings. The one pictured below and found in the National Maritime Museum, Greenwich, London dates from 1775 and is made of mahogany. It measures 35″ closed and when open is 44″ long. The opening holding the objective lens is 66mm, about 2.5″, in diameter. Hardly something you’d want to climb into the rigging holding.

As the science of metallurgy advanced, the telescope barrels of brass became more common. This next telescope, also from the National Maritime Museum, dates from about 1800 and is leather-covered brass some 25″ long when closed and 29″ long when opened. The end holding the objective lens is 44mm or about 1.7″ in diameter.

In the case of the brass telescope, the handiness of lopping some 15 inches off the extended length is a radically reduced field of vision.

Another interesting innovation was the development of the night telescope, or night glass. Using a conventional telescope at night is difficult because the relatively small objective lens did not permit a lot of light to enter the tube and interior lenses which were required to correct the inverted image produced by a simple refracting telescope absorbed part of that light. The result was a telescope with a fairly large objective lens but which produced an image that was inverted,

The below example of a night telescope dates from 1810, it has a leather tube with brass fitting. It measures 28″ long closed and 34″ when extended. The end holding the objective lens is 82mm, or nearly 3.25″.

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17 Comments

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17 responses to “Naval Telescopes

  1. Pingback: Naval Telescopes « Age Of Sail | NavalArts.Com

  2. brian buckman

    I am a collector of British naval telescopes. I am looking for some source that references standard Admiralty patterns for manufacturers to use strting from the 1880′s onward. I would appreciate any suggestions

  3. Mr Ian Ladds

    I am trying to find some information on two telescopes we have .
    First is a W.Watson & son –1916 ,No 5278
    sighting telescope No4 Mk III with the
    Goverment arrow . ex father-in-law .
    The 2nd is a H . Hughes & sons Naval telescope of
    my grandfathers No 417a/3969

    • Lee Barnard

      I also have a H . Hughes & sons brass and leather naval telescope that beldonged to my grandfather. Unfortunately the lens at the end is missing. I would love to know what it looked like as I am thinking of looking for a specialist who could replace it.

      • Lee Barnard

        Mine is engraves: H.(enry) Hughes and Son, 59, Fenchurch St., London. That was the makers address between 1879-1941.

  4. roccaas

    Does anyone have information on the “Come Up” telescope that Jack Aubrey employs from the upper yards to determine if he is overtaking a prize? I cannot cite the volume in O’Brian’s series where this event took place, but the scope had two (2) images side by side of the chase. If one were overtaking, one of the images would superimpose (?) over the other or some such optical magic.

    Google, Wiki, ePay, and Amazon have not been able to help me in finding information or sources about this fascinating piece of equipment.

    Thank you

    “What a fascinating modern world we live in!”

  5. naturally like your web site however you need to test the spelling on several of your posts. A number of them are rife with spelling problems and I in finding it very bothersome to inform the reality on the other hand I’ll certainly come again again.

  6. hello
    frith naval telescope is from ?

  7. Anthony Ashmore is referring to a review in The Philosophical Magazine v22 issue 88, starting on page 319. It takes some work, but you can find the full PDF for this issue on google books.

  8. Daniel Morris

    I am interested in information on a lot of recently purchased antique telescope eyepiece tubes, which are all marked U.S. Navy. Almost all of the tubes are marked 12.5X and appear to be from Officer of the Watch type telescopes that have not been a focus of my collection. Additional research on the manufactures suggested almost all may be from actual civil war telescopes. Most specifically, A. Bardou appears to have changed to Bardou & Sons prior to the civil war.

    The manufactures were:
    Queen & Co. (2 scopes)
    A. Bardou Paris (8)
    Bardou & Sons Paris (3)
    Dubois & Co. Paris (3)

    Perhaps most interestingly one scope is labeled only Sig. Dept. U.S.A. This scope has a complete eyepiece lens set and two additional draws. It appears to be of high quality as the two large tubes are perforated and the internal threads are set down inside the telescope.

    Other than that, there are no objective lenses and only a few battered partial main tubes, but I am hesitant to start stripping the scopes for lenses until I determine if they have historic value.

    If you (or anyone you know of) might address this issue, I could use some guidance.

  9. Chris Marples

    Hello! Can someone advise, please? In the 1950′s, when I was in my early teens, an uncle on his deathbed sent me a brass telescope via my parents. I was told that it was “a night glass from the HMS Iron Duke”. I still have the telescope, in full working condition. Only the lens cap is damaged.

    Can anyone shed any light? Is it likely to be the real thing, or fake? I can discover no connection between my uncle and the navy. My interest is aroused just now by the WW1 publicity.

    Thanks! Chris Marples

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