United States or Libya ? Vote for the TOP Country of the Week !
The suitable mounting of this vast machine was a problem scarcely less difficult than its construction. The shape of a speculum needs to be maintained with an elaborate care equal to that used in imparting it. In fact, one of the most formidable obstacles to increasing the size of such reflecting surfaces consists in their liability to bend under their own weight.
Under his feet the likeness of three books which he compiled; the first named Speculum Meditantis, written in French; the second Vox Clamantis, in latin; the third Confessio Amantis, in English; this last piece was printed by one Thomas Berthalette, and by him dedicated to King Henry VIII. His Vox clamantis, with his Chronica Tripartita, and other works, both in Latin and French, Stow says he had in his possession, but his Speculum Meditantis he never saw.
It was called a speculum oris. The dotted lines in the figure on the right hand of the screw represent it when shut, the black lines when open. It is opened, as at G H, by a screw below with a nob at the end of it. This instrument is known among surgeons, having been invented to assist them in wrenching open the mouth as in the case of a locked jaw; but it had got into use in this trade.
"I'm glad of it, boy, because I don't want what the Germans call a dummkopf to help me. I see; I must volunteer my information. To begin with then, that disc of glass is " "For the speculum," said Tom eagerly; "and you're going to polish it." "Wrong. That's only for the tool. The other is for the speculum, and we are going to grind it upon the tool."
The great reflectors of Herschel and Lord Rosse, which were provided with mirrors of speculum metal, were far inferior to much smaller telescopes of the present day. With these instruments the star images were watched as they were carried through the field of view by the earth's rotation, or kept roughly in place by moving the telescope with ropes or chains.
As soon as the entire surface of the mould plate was covered by the alloy, its weight overcame that of my up-tilting counterpoise, and allowed the entire apparatus to resume its exact level. The resulting speculum was, by these simple arrangements, absolutely perfect in soundness.
In 1585 Fabricius de Hilden invented the speculum auris. This instrument was employed by him for the first time under the following circumstances: A girl ten years of age had in playing introduced a small glass ball into her left ear, and four surgeons, called in successively and at different times, had been unable to extract it.
The second in p. 42, is a relation taken from the Speculum Historiale of Vincentius Beluacensis, lib. xxxii. ch. 2. of the mission of certain friars, predicants and minorites in the same year, 1246, to the same country; and in p. 59. of the same collection, there is a translation by Hakluyt into antiquated English of this second account.
That afternoon, and for an hour and a half in the evening, they worked again at the speculum by lamp-light, so that Tom was pretty tired when they gave up and returned to the cottage. "Going to watch for the fruit burglar to-night, Tom?" asked Uncle Richard. "Oh yes, uncle.
It was cast with perfect soundness, and was ground and polished by a machine which I contrived for the purpose. The speculum was so brilliant that when my friend William Lassell saw it, he said "it made his mouth water." It was about this time that I had the great happiness of becoming acquainted with Mr. Lassell was a man of superb powers.
Word Of The Day