The monster telescopes, erected by the earl of Rosse, Parsonstoun1845 |
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The Monster Telescopes, Erected by the Earl of Rosse, Parsonstoun Thomas Woods No preview available - 2016 |
Common terms and phrases
affecting the mirror allow anneal arrangement attempted axle beam brass bed cast iron centres of gravity chain cold water compound Speculum connected cool the metal counterpoise course crucible dicular Dublin Evening Mail Dublin Evening Packet Earl of Rosse effect emery and water excentric feet in diameter feet long fixed fluid focal length full of flaws fused gallery grinding and polishing grooves ground hang heat horizon inch and a-half instrument iron bottom iron circle jet of cold layers of hoop-iron lever LORD ROSSE Lord Rosse's Lordship's machinery manner manufacture melted metal gradually MONSTER TELESCOPES mould move Nebulæ number of Specula oven PARSONSTOWN perfectly perpendicular position pieces pitch plates points prevent produced pulley rack rendered resin right ascension runs Sal Ammoniac sand seen SHEILDS side soldered Speculum box Speculum metal spirit level strain success sufficiently temperature THOMAS WOODS three foot Speculum turned turpentine universal joint vessel of lime wall weight windlass
Popular passages
Page 16 - formula practically valuable : this I have endeavoured to accomplish." The grinding of the Speculum to the proper figure then depends on the relative velocities of the different parts, as before stated. The substance made use of to wear down the surface was emery and water; a constant supply of these was kept between the grinder and the Speculum.
Page 3 - species of brass, which expanded in the same degree by heat as the pieces of the Speculum themselves; they were then ground as one body to a true surface, and when polished were found to answer remarkably well. The particulars in the manufacture of this compound Speculum requiring attention are, First—The method employed to find
Page 35 - X is a railroad on which the Speculum is drawn either to or from its box—part is cut away to show the counterpoise. The dotted line, a, represents the course of the weight
Page 13 - the Speculum with a force equal to the difference between its own weight and that
Page 13 - centre. At M there is a swivel and hook, to which a rope is attached, connecting the whole with the lever, N, so that the polisher presses
Page 37 - always equal to the varying weight. Under these circumstances we see how easily and evenly the windlass can elevate the Telescope, and turn it to the north; but when it arrives there it must be brought back again; and this
Page 36 - but the labour of this would be immense if the counterpoise K did not assist: this nearly balancing the tube, leaves but little exertion to be made at the windlass. However, the weight of the tube according as it ascends,
Page 35 - the tube rises or falls; it is a segment of a circle of which the chain I is the radius. With a little attention to these several points, the working of the machinery, will, we think, be easily comprehended. We must first state that the Speculum is supported on three screws, which pass from the universal joint through the bottom of the box in which it lies, and is
Page 9 - 0 th of an inch apart—all was allowed to cool gradually, and in five days it was ready to be ground. The casting of a Speculum, and its preservation from breaking when cooling, has always been found a matter of the greatest difficulty. The compound is so
Page 13 - M is a round disk of wood, connected with the polisher, by strings hooked to it in six places, each