The school of arts; or, an introduction to useful knowledge1796 |
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Common terms and phrases
againſt alfo alſo atmoſphere axis ball barrel becauſe body brafs braſs cafe cauſe concave condenfer confequently confiderable confifts convex convex lens cylinder defcend diameter diſcharge eafily earth ecliptic electric fluid electrometer equal exhaufted eye-glafs faftened fame fcrew fecond feen feet fhew fhould fide filk firft firſt fixed flider fmall focal diſtance focus folar fome force fquare ftands fteam fuch fufficient fuppofe furface glafs glaſs greateſt hole hydrometer inches increaſe infide inftrument itſelf knob lefs length lens machine magnifying mercury microſcope mirror moft moon motion move muft muſt nodes obferved paffing paſs pencil perfon piece pifton pinion pipe plane plate pofition preffed preffure prime conductor pulley pump purpoſe quickfilver raiſed rays repreſented retina rife round ſcale ſcrew ſmall ſpring teeth teleſcope thefe theſe thofe thoſe tube turn uſe valve veffel weight wheel whofe wire
Popular passages
Page 111 - ... 6. In fair weather, when the mercury falls much and low, and thus continues for two or three days before the rain comes, then expect a great deal of wet, and probably high winds.
Page 115 - Va" pours are better kept fufpended, fo that they " have no Inclination to precipitate and fall " down in Drops, which is the Reafon of the " ferene good Weather which attends the " greater Heights of the Mercury. " 3. The Mercury finks the loweft of all by " the very rapid Motion of the Air in Storms
Page 108 - Set a lighted candle upon the pump, and cover it with a tall receiver. If the receiver holds a gallon, the candle will burn a minute ; and, then, after having gradually decayed from the first...
Page 158 - The condenfer confifts of one or more pumps furnifhed with clacks and buckets, (nearly the fame as in common pumps) which are wrought by chains faftened to the great working beam of the engine. The pipe, which comes from the cylinder, is joined ;to the bottom of thefe pumps, and the whole condenfer ftands immerfed in a ciftern of cold water fupplied by the engine.
Page 55 - ... the jar to difcharge itfelf. If the coating is about two inches below the top, it will in general do very well; but there are fome kinds of glafs, efpecially tinged glafs, that, when coated and charged, have the property of difcharging themfelves more eafily than others, even when the coating is five or fix inches below the edge.
Page 8 - When the prop is at one end of the lever, the power at the other, and the weight between them.
Page 122 - Universally, therefore, a body plunged in water, loses as much of its weight as is equal to the weight of a body of water of its own bulk.
Page 149 - ... natural position, with respect to other objects which we see and compare it with. If we lay hold of an upright stick in the dark, we can tell which is the upper or lower part of it, by moving our hand upward or downward; and know very well that we cannot feel the upper end by moving our hand downward.
Page 139 - ... as high as the leather which covers the bellows will allow them, the water will remain in the pipe, and fupport all the weights, even though it fhould weigh no more than a quarter of a No.
Page 115 - The greater height of the barometer is occafioncd by two contrary winds blowing towards the place of obfervation, whereby the air of other places is brought thither and accumulated ; fo that the incumbent cylinder of air being...