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Página i - WORKSHOP COMPANION. Comprising a great variety of the most useful Rules and Formulae in Mechanical Science, with numerous Tables of Practical Data and Calculated Results for Facilitating Mechanical Operations. By WILLIAM TEMPLETON, Author of " The Engineer's Practical Assistant, "&c., &c. Eighteenth Edition, Revised, Modernised, and considerably Enlarged by WALTER S. HUTTON, CE, Author of "The Works' Manager's Handbook," " The Practical Engineer's Handbook,
Página 28 - Square Measure. 144 square inches 1 square foot, 9 square feet 1 square yard, 30J square yards 1 square rod, 40 square rods 1 rood, 4 roods 1 acre.
Página 100 - MECHANICAL POWERS are certain simple instruments employed in raising greater weights, or overcoming greater resistance than could be effected by the direct application of natural strength. They are usually accounted six in number; viz. the Lever, the Wheel and Axle, the Pulley, the Inclined Plane, the Wedge, and the Screw.
Página 110 - The wedge is a double inclined plane ; consequently, its principles are the same- Hence, when two bodies are forced asunder by means of the wedge, in a direction parallel to its head, multiply the resisting power by half the thickness of the head or back of the wedge, and divide the product by the length of one of its inclined sides ; the quotient is the force equal to the...
Página 92 - To find the absolute strength of a rectangular beam, when fixed at one end and loaded at the other. RULE. Multiply the value of S by the depth of the beam, and by the area of its section, both in inches: divide the product by the leverage in inches, and the quotient equal the absolute strength of the beam in Ibs.
Página 35 - From half the sum of the three sides subtract each side ; multiply the half sum and the three remainders together, and the square root of the product will be the area required.
Página 95 - Resistance of bodies to flexure by vertical pressure. When a piece of timber is employed as a column or support, its tendency to yielding by compression is different according to the proportion between its length and area of its cross section ; and supposing the form that of a cylinder whose length is less than seven or eight times its diameter, it is impossible to bend it by any force applied longitudinally, as it will be destroyed by splitting before that bending can take place ; but when the length...
Página 47 - RULE. To twice the length of the base, add the length of the edge, multiply the sum by the breadth of the base, and this product by the perpendicular height of the wedge ; and | of the last product will be the solidity.
Página 124 - When no unguent is interposed, the amount of the friction is, in every case, wholly independent of the extent of the surfaces of contact ; so that, the force with which two surfaces are pressed together being the same, their friction is the same, whatever may be the extent of their surfaces of contact.
Página 90 - ... in Ibs. by the cube of the length in feet; divide the product by 32 times the tabular value of E, multiplied into the given deflection in inches ; and the quotient is the breadth multiplied by the cube of the depth in inches.