OF RULES, TABLES, AND DATA FOR MECHANICAL ENGINEERS BASED ON THE MOST RECENT INVESTIGATIONS: OF CONSTANT USE IN CALCULATIONS AND ESTIMATES RELATING TO STRENGTH OF MATERIALS AND OF ELEMENTARY CONSTRUCTIONS; LABOUR; THE WEIGHT OF BODIES; WEIGHT OF METALS, &C. WITH TABLES OF LOGARITHMS, CIRCLES, SQUARES, CUBES, SQUARE-ROOTS, AND CUBE-ROOTS; BY DANIEL KINNEAR CLARK, MEMBER OF THE INSTITUTION OF CIVIL ENGINEERS; AUTHOR OF "RAILWAY MACHINERY," "EXHIBITED MACHINERY OF 1862," ETC. BLACKIE & SON: PATERNOSTER BUILDINGS, GLASGOW AND EDINBURGH. All Rights Reserved. 11578 TED PREFACE. THIS Work is designed as a book of general reference for Engineers: -to give within a moderate compass the leading rules and data, with numerous tables, of constant use in calculations and estimates relating to Practical Mechanics. The Author has endeavoured to concentrate the results of the latest investigations of others as well as his own, and to present the best information, with perspicuity, conciseness, and scientific accuracy. Amongst the new and original features of this Work, the following may be named: In the section on Weights and Measures, the weight, volume, and relations of water and air as standards of measure, are concisely set forth. The various English measures, abstract and technical, are given in full detail, with tables of various wire-gauges in use: and equivalent values of compound units of weight, power, and measure-as, for example, miles per hour and feet per second. The French Metric Standards are defined, according to the latest determinations, with tables of metric weights and measures, equivalents of British and French weights and measures, and a number of convenient approximate equivalents. There is, in addition, a full table of equivalents of French and English compound units of weight, pressure, time, space, and money-as, for example, pounds per yard and kilogrammes per metre; which will be found of great utility for the reciprocal conversion of English and French units. The tables of the Weight of bars, tubes, pipes, cylinders, plates, sheets, wires, &c., of iron and other metals, have been calculated expressly for this Work, and they contain several new features designed to add to their usefulness. They are accompanied by a summary of the various units of weight of wrought iron, cast iron, and steel, with plain rules for the weight. In the section on Heat and its Applications, the received mechanical theory is defined and illustrated by examples. The relations of the pressure, volume, and temperature of air and other gases, with their specific heat, are investigated in detail. The transmission of heat through plates and pipes, between water and water, steam and air, &c., for purposes of heating or cooling, is verified by many experimental data, which are reduced to units of performance. The physical properties of steam are deduced from the results of Regnault's experiments, with the aid of the mechanical theory of heat. A very full table of the Properties of Saturated Steam is given. The table is, for the most part, reproduced from the article "Steam," contributed by the Author to the Encyclopedia Britannica, 8th edition, and it was the first published table of the same extent, in the English language, based on Regnault's data. An original table of the properties of saturated mixtures of air and aqueous vapour is added. In the section on Combustion, new and simple formulas and data are given for the quantity of air consumed in combustion, and of the gaseous products of combustion, the heat evolved by combustion, the heating power of combustibles, and the temperature of combustion; with several tables. On Coal as a Fuel, both English and Foreign, its composition, with the results of many series of experiments on its combustion, are collected and arranged. The quantity of air consumed in its combustion, and of the gaseous products, with the total heat generated, are calculated in detail. Coke, lignite, asphalte, wood, charcoal, peat, and peat-charcoal, are similarly treated; whilst the combustible properties of tan, straw, liquid-fuels, and coal-gas, are shortly treated. The section on Strength of Materials is wholly new. The great accumulation of experimental data has been explored, and the most important results have been abstracted and tabulated. The results of the experiments of Mr. David Kirkaldy occupy the greater portion of the space, since he has contributed more, probably, than any other experimentalist to our knowledge of the Strength of Materials. The Author has investigated afresh the theory of the transverse strength and deflection of solid beams, and has deduced a new and simple series of formulas from these investigations, the truth of which has been established with remarkable force by the evidence of experiment. These investigations, based on the action of diagonal stress, throw light upon the element called by Mr. W. H. Barlow, "the resistance of flexure:" revealing, in a simple manner, the nature of that hitherto occult entity; and showing that flexure is not the cause, but the effect of the resistance. In addition to formulas for beams of the ordinary form, special formulas have been deduced for the transverse strength and deflection of railway rails, double-headed or flanged, of iron or steel; in the establishment of which he has availed himself of the important experimental data published by Mr. R. Price Williams, and by Mr. B. Baker. To our knowledge of the strength of timber, Mr. Thomas Laslett has recently made important additions, and the results of his experiments have been somewhat fully abstracted and analyzed. But woods, by their extremely variable nature, are not amenable, like wrought-iron and steel, to the unconditional application of formulas for transverse strength. The Author has, nevertheless, deduced from the evidence, certain formulas for the transverse strength and deflection of woods, with tables of constants, which, if applied with intelligence and a knowledge of the uncertainties, cannot fail to prove of utility. The Torsional Strength of Solid Bodies has also been investigated afresh, and reduced to new formulas. In dealing with the Strength of Elementary Constructions, the Author has brought together many important experimental results. In treating of rivet-joints and their employment in steam-boilers, he has, he believes, clearly developed the elements of their strength and their weakness. By a close comparison of the results of tests of cast-iron flanged beams, it is plainly shown that the ultimate strength of a cast-iron beam is scarcely affected by the proportionate size of the upper flange, and that the lower flange and the web are, practically, the only elements which regulate the strength. The tests of solid-rolled and rivetted wrought-iron joists are also analyzed; and for the strength and deflection of these, as for those of cast-iron flanged beams, new and simple rules and formulas are given. A new investigation, with appropriate formulas, is given for the bursting strength of hollow cylinders, of whatever thickness. It is shown that the variation of stress throughout the thickness, follows a diminishing hyperbolic ratio from the inner surface towards the outer surface. The resistance of tubes and cylindrical flues to collapsing pressure is also investigated, and formulas based on the results of experience are given. On the subject of Mill-gearing, a new and compact table of the pitch, number of teeth, and diameter of toothed wheels is given, with new formulas and tables for the strength and horse-power of the teeth of wheels, and for the weight of toothed wheels. New formulas and tables are given for the driving power of leather |