Elements of mechanism |
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angular velocity annexed fig arrangement ascend attached axes axis axle barrel boiler camb cast-iron centre of motion centrifugal force centripetal force chain circumference conical surfaces cord crank crown-wheel curve cylinder descends described diameter direction distance driving engine equa equal equation excentric feet fixed fly-wheel force formed frame friction frustums fulcrum gear girders groove gudgeons inches inclined inclined plane kiln lathe length lever machine machinery miles per hour moveable moved number of revolutions number of teeth P's vel parallel motion passing pinion pipe piston pitch circle plane plate pressure produced Prof pulley pump rack radii radius railway raised ratchet-wheel reciprocating motion revolve roller rope round screw shaft shown slide space spindle spur-wheel steam steam-engine sugar surface threads tons tooth train tube turned valve velocity ratio vertical vessels weight wheel whence Willis's Mechanism
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Trang 226 - MEASURING, and VALUING ARTIFICERS' WORKS; containing Directions for taking Dimensions, Abstracting the same, and bringing the Quantities into Bill, with Tables of Constants, and copious Memoranda for the Valuation of Labour and Materials in the respective Trades of Bricklayer and Slater, Carpenter and Joiner, Painter and Glazier, Paperhanger, &c.
Trang 225 - Practical Mathematics. MATHEMATICS for PRACTICAL MEN ; being a Commonplace Book of Pure and Mixed Mathematics. Designed chiefly for the Use of Civil Engineers, Architects, and Surveyors. Part I. PURE MATHEMATICS — comprising Arithmetic, Algebra, Geometry, Mensuration, Trigonometry, Conic Sections, Properties of Curves.
Trang 172 - ... leg, which column balances the pressure of steam in the boiler, or, more correctly speaking, it balances the excess of the pressure of the steam in the boiler, above that of the atmosphere ; in fact, the atmosphere, pressing through the open mouth of the tube upon the mercury in the longer leg, combines with the column of mercury xx in balancing the pressure of steam in the boiler. If, then...
Trang 172 - In high-pressure boilers, a mercurial gauge of the form shown in the preceding fig. would be inconvenient, owing to the great height of the column of mercury which would be necessary. In this case a gauge of another form is made use of, an example of which is shown in the annexed figure. Let AB be a cistern of mercury ; let t be a glass tube, open at the lower end and closed at the upper end, immersed in the mercury, and containing air in its ordinary state. When the stop-cock d is open, the steam...
Trang 62 - Thence the line follows south of the Benue, the circumference of a circle, the centre of which is the centre of the town of Yola as it existed in 1893, and the radius of which is the distance between the centre of the town of Yola and the point on the left bank of the Benue...
Trang 91 - B", the extremity D descends to D" ; thus the two extremities are again drawn, the one a little to the right, and the other a little to the left.
Trang 113 - ... c closed and open that at H, whence air will escape. By similar ascents and descents of the piston the air will be expelled and water rise into the body of the pump. The descending piston will then press the water through the valve at H, which will close and prevent its return into the body of the pump. The ascents and descents of the piston, being thus continued, will raise the water to any required height in the pipe H K.
Trang 169 - A, a large stem of malleable iron, centre die every description of flat or circular work can be riveted, and by selecting those on the sides it will rivet the corners, and thus complete vessels of almost every description. This machine is of a portable form, and can be moved on rails to suit the article suspended from the hook. This machine fixes in the firmest manner, and completes 8 rivets of J-inch diameter in a minute, with the attendance of two men and two boys ; whereas the average work that...
Trang 174 - ... the spring with a force equal to the excess of the pressure of the steam above that of the atmosphere. When, on the other hand, a vacuum is produced in the cylinder by the condensation of the steam, the same vacuum will be produced under the piston in the indicator, and the piston will be forced downwards by the excess of the pressure of the atmosphere above that of the uncondensed vapour in the cylinder. " If an index were placed near the extremity of the pistonrod t, the pencil, ascending and...
Trang 115 - ... and the friction of the wheel on its axis ; and, where a large quantity of water is to be raised to a moderate height, both of these resistances may be rendered inconsiderable.