Tin, Tin, Tin, Zinc........... Tin, 1 Zinc .......... Tin, 10 Zinc, Indian 1 1.371 12,914 7.288 Musch. Intr. ad Phil. Nat. 1 1.595 15.025 7.000 Idem. 1 Zinc.......... 10 0.602 5,671 7.130 Idem. Tin, English 1 Zinc, Goslar 1 0.958 9,024 [i. 444. Musch. Intr. ad Phil. Nat. Tin, 2 Zinc 1 1.164 10,964 Idem. [i. 446. Idem. Idem. Tin, 1 Antimony... 1 Tin. Tin, 0.154 1,450 7.000 Musch. Intr. ad Phil. Nat. 3 Antimony.. 2 0.338 3,184 4 Antimony... 1 1.202 11,323 LINEAR DILATATIONS BY HEAT. Dimensions which a bar takes at 212°, whose length POWER OF CONDUCTING at 32° is 1.000000; also its dilatation in vulgar From Despretz's Experiments.* fractions. Platinum................ 1.00091085 or one 1097th part. Conducting power. Gold 100 Palladium....... Antimony.... ............ 1.00100000 ......................................... 1.00108300 66 1000th 66 97.3 Cast iron................. 1.00111025 901st "6 Copper 89.82 824th 66 801st 66 Zinc 36.37 Bismuth........................................... 1.00139200 1.00149824 66 Brass....... Copper... 1.00179633 66 557th 66 2.34 " 550th Porcelain....... 1.22 524th 66 66 517th " 1.00200183 66 499th "6 Lead..... 1.00285768 Zinc....................... 1.00297650 The above are the mean proportions of the various examples of each metal, given in Ure's Dictionary of Chemistry and elsewhere. * Ann. de Chim. et de Phys. xix. 97. + Traité Elémentaire de Physique, par M. Despretz, p. 20, as quoted by Dr. Thomson, on Heat and Electricity, p. 103. 424th 44 336th WEIGHTS OF WROUGHT-IRON, STEEL, COPPER, AND BRASS WIRE AND PLATES. The specific gravities to determine the weights of the followingnamed metals, and the calculations of them, were taken and made by Charles H. Haswell, of New York, for the well-known manufacturers, Messrs. J. R. Brown & Sharpe, of Providence, R. 1. Diameter and thickness determined by American gage: CHAPTER XIII. REMARKS ON THE CHARACTERS OF THE METALS AND ALLOYS. HARDNESS, FRACTURE, AND COLOR OF ALLOYS.-The object of the present chapter is to explain in a general way some of the peculiarities and differences amongst alloys, prior to entering on the means of melting the metals, without which process alloys cannot be made: yet notwithstanding that the list contains the greater number of the alloys in ordinary use, and many others, it is merely a small fraction of those which might be made. It is also stated that metals appear to unite with one another in every proportion, precisely in the same manner as sulphuric acid and water. Thus there is no limit to the number of alloys of gold and copper. The same might be said of many other metals, and when the alloys compounded of three, four, or more metals, are taken into account, the conceivable number of alloys becomes almost unlimited. It is certain, however, that metals have a tendency to combine in definite proportion; for several atomic compounds of this kind occur native. It is indeed possible that the variety of proportions in alloys is rather apparent than real, arising from the mixture of a few definite compounds with each other, or with uncombined metal; an opinion not, only suggested by the mode in which alloys are prepared, but in some measure supported by observation. It appears to be scarcely possible to give any sufficiently general rules, by which the properties of alloys may be safely inferred from those of their constituents; for although, in many cases, the working qualities and appearance of an alloy, may be nearly a mean proportional between the nature and quantities of the metals composing it; yet in other and frequent instances the deviations are excessive, as will be seen by several of the examples referred to. Thus, when lead, a soft and malleable metal, is combined with antimony, which is hard, brittle, and crystalline, in the proportions of from twelve to fifty parts of lead to one of antimony; a flexible alloy is obtained, resembling lead, but somewhat harder, and which is rolled into sheets for sheathing ships. Six parts of lead and one of antimony are used for the large soft printers' types, which will bend slightly, but are considerably harder than the foregoing; and three parts of lead and one of antimony are employed for the smallest types, that are very hard and brittle, and will not bend at all; antimony being the more expensive metal, is used in the smallest quantity that will suffice. In this alloy the antimony fulfills another service besides that of mparting hardness: antimony somewhat expands on cooling, |