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In 1870 my father became acquainted through the English Mechanic with Dr. Blacklock* and this gentleman gave him advice regarding the building of his telescopes; but it was all done by letter, for they never met,and it was wonderful how Dr. Blacklock found time with all his work to write so many letters as he did. Father also received letters from Mr.Nasmyth**, the inventor of the steam-hammer, on the same subject. Mr.Nasmyth took great interest in him and would write two or three sheets at a time, pointing out the difficulties and explaining how they might be overcome, and drawing diagrams of the tools he would need. Afterfather had made the speculum, which he found exceedingly difficult, it had to be silvered on the front surface; and on this point Dr. Blacklockgave him valuable information which enabled father to do it successfully at the very first attempt.

*Dr. A. Wolsley Blacklock of Ipswich. "The English Mechanic and Mirror of Science and Art", published monthly at the price of 2d. would today have been replaced by a blog. The spirit of the magazine  could be  summed up by this phrase: "Contributions from working men, noblemen and the greatest living scientists appear side by side in the same issue, all men bound together in a brotherhood of mutual help."

Anyone and everyone contributed on any subject they chose, writing out of their own personal experience, but  writing under a pseudonym. The article which first caught Roger Langdon's attention was titled "Speculum Casting and Grinding". It led to many years of correspondence between the two men and much generous assistance by Dr. Blacklock.

** James Nasmyth, famed for his skill and talent as an engineer. always described himself first and foremost as an astronomer. He too was a very generous friend to Roger Langdon.

In 1874 father made a model in plaster of Paris of the visible hemisphere of the moon, showing five hundred principal objects, hollows, craters, and mountains. This model he afterwards presented to the Devon and Exeter Institute. Mr. C. R. Collins of Teignmouth once wrote an article describing the discovery of a new crater on the moon by Dr.Hermann J. Klein of Cologne. Going to his observatory father was able to show on this model of the moon, as the result of his own observations, this very crater.

Father had now made two telescopes, but he hoped to make another and still better one; so he set to work, and it was in the making of this that he received so much valuable advice from Mr. Nasmyth and Dr.Blacklock.


This third telescope was a beautiful instrument. It had a six-inch speculum with a five foot focal length. With this he was enabled to detect certain markings upon the planet Venus. In 1871 he read a paper before the Royal Astronomical Society in London upon this subject. He said afterwards that he never was so nervous in his life as on this occasion, and he wished the earth would open and swallow him up. But his paper was very well received, and commended.[1] He also made over athousand drawings and photographs of the moon's surface.


* [1] Webb quotes from this paper in his book "Celestial Objects for Common Telescopes". My father's observations are also mentioned in Clarke's "History of Astronomy During the Nineteenth Century".



Much as father had accomplished, he was still bitten with the idea tha this telescope was not so good as he would like, although it was a splendid one, and had cost him many weary hours' hard work to make. So he sold it for £10, and in the year 1875 set about making his fourth telescope--a very noble instrument, for which he had to build an observatory. He describes it thus: "An 8-1/4-inch silver-on-glass reflector mounted in a stout zinc tube, which turns in a cast-iron cradle on its own axis. The focal length is seven feet. There is a diagonal place for viewing the stars and a specially prepared glass wedge for observing the sun. The whole is mounted as an equatorial upon a strong cast-iron stand. It had two stout brass right ascension circles divided to 10 seconds, and declination circles divided to 5 minutes of arc. The telescope is furnished with a driving clock which keeps the celestial object in the field of view. The observatory is a circular iron building with conical-shaped revolving roof, two swing flaps of which give the required opening to the sky."


This telescope took a long time to make, and night after night through many a weary month, when station duty was done, father would work at it for hours together in his home-made work-shop. But, as usual, the want of funds hampered him a good deal, and he found many difficulties to overcome; but he worked away with intense enthusiasm, and with the advice of Dr. Blacklock and Mr. Nasmyth, he at last completed this Newtonian equatorial reflecting telescope fitted with a finder with Ramsden eye-piece. He added to it a trap for taking photographs, the invention of his own brain, and in visiting Greenwich Observatory some years later he was pleased to find that the apparatus in use there for the same purpose was almost identical with his own. With this telescope
my father photographed the transit of Venus and took also several pictures of the sun and of the moon.

To make his first telescope in 1865 he bought some second-hand lenses for a few shillings, and by means of a turning lathe he turned a stick upon which to roll the tin case, according to the size of the lens.

The second telescope was a much more difficult undertaking for one whose acquaintance with mechanical processes was entirely self-acquired. He was as a man groping in the darkness. To obtain the special glass necessary for the speculum; to grind it to the most delicately accurate
shape and density; to polish and silver the speculum; to make the metal tube to the requisite size and scale; to mount it with the necessary adjustments and accuracy; all these were so many enigmas which only his intense enthusiasm and perseverance enabled him to solve.



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