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Updated: May 22, 2025
In what follows I have only a refractor in mind, although the same principles would apply to a reflector. With a little practice anybody who has a correct eye can form a fair judgment of the excellence of a telescopic image. Our first object is to see if the optician has given us a good glass.
By turns they put on the glass surface hairs, tobacco, finger-nails, and a fly's claw, but they forgot the drop of water which is indispensable; at other times it was the little lamel, and they pushed each other forward, and put the instrument out of order; then, when they saw only a haze, they blamed the optician. They went so far as to have doubts about the microscope.
Between eight o'clock and midnight one optician in Jones'-Fall Street made his fortune by the sale of opera-glasses. Midnight arrived, and the enthusiasm showed no signs of diminution. It spread equally among all classes of citizens men of science, shopkeepers, merchants, porters, chair-men, as well as "greenhorns," were stirred in their innermost fibres. A national enterprise was at stake.
A shallow tray was contrived deep enough to hold the speculum, and fitted with screws, so that it could be secured to one end. Next followed the fitting of a properly-constructed eye-piece from a London optician, contrived so that it looked at right angles into a small reflector, which also had to be carefully fixed in the axis of the great speculum.
Ramsden had fallen into bad health, and the Board considerately directed that "inquiries should be made." Next year there was still no progress, so the Board were roused to threaten Ramsden with a suit at law; but the menace was never executed, for the malady of the great optician grew worse, and he died that year.
It seems probable that the seven-foot telescope constructed by him in 1775 that is within little more than a year after his experiments in shaping and polishing metal had begun already exceeded in effective power any work by an earlier optician; and both his skill and his ambition rapidly developed.
The Optician and the Oculist have studied the matter so carefully and know the eye so thoroly in its various stages of development that they know exactly the size of type that children of various ages should use. And they know, too, the kind of paper that should be used in books for children. And they have told us all about it.
Now it happened that Nicholas Forster, of whom we have already made slight mention, although he considered at the time of his marriage that the person he had selected would exactly suit his focus, did eventually discover that he was more short-sighted in his choice than an optician ought to have been.
Once in possession of a perfect object-glass, the rest of the telescope is a matter of little more than constructive skill which there is no difficulty in commanding. The construction of the object-glass requires two completely distinct processes: the making of the rough glass, which is the work of the glass-maker; and the grinding and polishing into shape, which is the work of the optician.
He was of the sort who combine enthusiasm with long-suffering, who, after each check, set about organizing the victory that is impossible, but is bound to come. And verily they must win the day. These men of no account, who had destroyed Royalty and upset the old order of things, this Trubert, a penniless optician, this Évariste Gamelin, an unknown dauber, could expect no mercy from their enemies.
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