Lectures on Select Subjects in Mechanics, Hydrostatics, Hydraulics, Pneumatics, Optics, Geography, Astronomy, and Dialling, المجلد 2Stirling & Slade, and Bell & Bradfute, 1823 - 400 من الصفحات |
طبعات أخرى - عرض جميع المقتطفات
عبارات ومصطلحات مألوفة
achromatic acting angle aperture arch axis axle azimuth beam brass buckets centre of gravity circular circumference colours concave concave lens construction contrivance convex convex lens Coulomb crystal curve cylinder diameter diminished direction double refraction effect employed epicycloid equal experiments eye-glass eye-piece feet fixed float-boards focal length force force of impulsion friction gudgeons horizontal horses inches inclined increase iron Klaproth lens lenses lever light load machine metal millstone motion move Newtonian telescope object-glass perpendicular pinion pipe piston pivot placed plane of reflexion polarised polished position pounds pressure prism produced proportional pulley quantity radius raised ratio rectilineal refracting telescope resistance rope round sails screw shewn in Fig sine speculum square steam Strength of Materials surface tallow Tang teeth telescope thickness tints tion torsion tube turning valve velocity vertical weight wheel wind wire
مقاطع مشهورة
الصفحة 114 - A Description and Draught of a new-invented Machine, for carrying Vessels or Ships out of, or into, any Harbour, Port, or River, against Wind and Tide, or in a calm.
الصفحة 322 - Jtint 14.2, the focal length of the combination being 10.00, and the radii of the interior surfaces being computed from these data, by the formulae given in all elementary works mi optics, so as to make the focal lengths of the two glasses in the direct ratio of their dispersive powers.
الصفحة 284 - ... our situation unavoidably inspired. This appeared to me the more remarkable, as my case was totally the reverse. I was in a state of excitement resembling the effect of some spirituous liquor. I suffered no pain ; I experienced only a strong pressure round my head, as if an iron circle had been bound about it. I spoke with the workmen, and had some difficulty in hearing them. This difficulty of hearing rose to such a height, that during three or four minutes I could not hear them speak. I could...
الصفحة 107 - ... alternately admitting the steam to the different sides of the smaller piston, while the steam last admitted into the smaller cylinder passes alternately to the different sides of the larger piston in the larger cylinder, the top and bottom of which are made to communicate alternately with the condenser. In an engine working with the improvements which have been...
الصفحة 284 - To remedy that inconvenience, the workmen instructed us, after havingclosed our nostrils and mouth, to endeavour to swallow, and to restrain our respiration for some moments, in order that, by this exertion, the internal air might act on the Eustachian tube. My companion, however, having tried it, found himself very little relieved by this remedy. After some minutes, we resumed our descent. My friend suffered considerably; he was pale; his lips were totally...
الصفحة 34 - ... of the wheel. 7. Then, as the number of revolutions of the wheel in a minute is to the number of revolutions of the millstone in a minute, so must the number of staves in the trundle be to the number of teeth in the wheel in the nearest whole numbers that can be found.* 8.
الصفحة 90 - I have seen the water run like a constant fountain stream forty feet high ; one vessel of water rarefied by fire driveth up forty of cold water. And a man that tends the work is but to turn two cocks, that one vessel of water being consumed, another begins to force and re-fill with cold water, and so successively, the fire being tended and kept constant, which the self-same person may likewise abundantly perform in the interim between the necessity of turning the said cocks.
الصفحة 106 - ... pounds the square inch entering above the smaller piston, will carry it downwards, while the steam below it, instead of being allowed to escape into the atmosphere or applied to any other purpose, will pass into the larger cylinder above its piston, which will take its downward stroke at the same time that the piston of the smaller cylinder is doing the same thing ; and while this goes on, the steam which last filled the larger cylinder, in the upward stroke of the engine, will be passing into...
الصفحة 98 - M, where it meets the jet of the injection from the cock N, and is reduced to water; and, in the lower...
الصفحة 61 - B, are two apertures in opposite directions. When water from the millcourse MN is introduced into the tube TT, it flows out of the apertures A, B, and by the reaction or counterpressure of the issuing water, the arm AB, and consequently the whole machine, is put in motion.