474 



METALLURGY. 



far superior to those exhibited by a piece of 

 iron. 



Vanadium, previously known only as a gray 

 powder including hvdrogen, oxygen, and a little 



. til kul i metal as impurities, has be : 

 intci | licet* having H crystalline ami brilliant 

 fracture, and is very difficult to melt. 



Titanium, produced with current.* of from 100 

 to 800 horse power from a f charcoal 



ami ii- . first as a crystal lized carbide. 



and then as the real metal, exhibit- <i: 

 pr<>|xTties from those formerly attributed to the 

 wders that bore its name. It takes fire 

 in DoorilM : decomposes water only at a bright- 

 it ; I. urns in nitrogen at a high tempera- 

 ture, yielding nitride of titanium: and readily 

 A nli carbon and silicon, but docs not 

 unite with argon. It resembles carbon in hav- 

 ing a very high melting point, but differs from 

 it in the fact that while carbon under the ordi- 

 nary pressure and at a great elevation of tem- 

 perature passes from a solid to a gas without 

 becoming liquid, titanium can. in the eleetri.- 

 furnace, be liquefied and then volatilized. 

 "Most of these simple bodies furnish, with car- 

 bon, well-defined combinations, crystallized and 

 stable at a high temperature, which are destined 

 to furnish a new chapter to mineral chemistry. 

 All these simple bodies which we have obtained 

 in the electric furnace form also borides and 

 silieides finely crystallized, and so hard that 

 some of them easily cut the diamond. What 

 part they are to have in the manufacture of 

 steel, and whether they are destined, like chro- 

 mium, to give new properties to iron are Questions 

 for the future to answer. But a new chemistry 

 of high temperatures is forming from which in- 

 dustry will most likely draw numerous appli- 

 cations." 



It has been pointed out by Spring that many 

 metals exhibit properties characteristic of the 

 limiid state, even when at temperatures much 

 below their melting points. In his experiments. 

 thfe metals were in the form of cylinders with 

 perfectly plane ends, placed end to end in an 

 iron holder, and forced together by means of a 

 screw while heated in an air bath or in a bath 

 of an indifferent gas. The metals used were 

 aluminum, bismuth, cadmium, copper, tin, gold, 

 lead, zinc, antimonv, and platinum. In the 

 earlier experiments both cylinders were of the 

 same metal, and the temperature was kept at 

 -'00* to 400 3 for from four to eight hours. 

 It was then found that, with the exception of 

 the platinum and antimony, the cylinders were 

 welded so perfectly that when one end was fixed 

 in a lathe the entire cylinder could be turned. 

 nnd when broken in a vise the fracture was not 

 through the line of separation. When different 

 metals were employed, as copper or lead with 

 certain other*, an alloy of considerable thickness 

 wan produced, 18 millimetres in the case of zinc 

 and copper, and 15 millimetres in that of cad- 

 mium and copper. When lead and tin were used 

 a cavity was made at one end of the cylinder 

 and when filled with mica, in order that contact 

 mid take place only at the edge, the allov 

 formed had a thickness of 15 millimetres, ! mil- 

 limeires being in the tin and 6 in the lead. With 

 eyliadtn of copper and zinc having a central 

 cavity at the ends in contact, the surface of the 



copper next to the cavity was colored \ . ; 

 sem hi ing the alloy formed when copper is ex- 

 posed to zinc vapor. These results are ex p! 



on t| M . a>suinpti"n that the molecules of SOliE 

 like those of Hinds, have not all tin 

 velocity. 



In a "lecture describing rusts, 1'r f. Skiilm..n-. 

 of Philadelphia. observed that it is not possw 



:;ue exactly what a metal is. jet therein 

 little liability to mistake in identifyin 

 The metallic* properties of b. .hues*, 



fusibility, opaqueness, conductivity, and rfZ 

 may be possessed separately by n on met a 

 they are not associated as they are in metm 

 Most metals maybe bent, twisted, draw i 

 hammered to an extent far bey. .ml wi... 

 mineral not a metal can endure. Sodii. 

 tassium, lithium, and. in a 1< 

 um, strontium, and barium, rust instantly WJH! 

 exposed to moist air, and their white ro2 

 juickly dissolve in water and form alkalies. 

 Another group including /inc. lead, magm 

 sium, and antimony have white ru-N t 

 not soluble in water, but form a thin a<: 

 coating, which only half conceals the me ! 



t a dull, Garnished appearance. At h -IHT 

 temperature than the ordinary, and -i 

 if tne metals are finely divided, the < 1 

 energy of rusting is so great that the 

 burn with a vivid light and emit a <i 

 smoke. The permanency of tiie-e ru-t-amlil 

 protective character are utilized in fan 

 third group of metals among which a; 

 per, iron, and silver have dark or colored rusts. 

 A fourth group, including gold and platinum. 

 never rust; they are found as in 

 earth, and not 'as ores from which the DMM 

 must be manufactured. It is an advantage 

 in the case of the other metals that 1) 

 found in the rust or ore condition, for ti 

 be manufactured more easily than they COJP 

 be cut from ledges of the pure metal. 



M. Ibnri Moissan has found, in hi 

 the solubility of carbon in different m< 

 in the same metal at temperature 

 more elevated, that boron and silicon di 

 displace carbon in cast iron and in melted ir^i 

 carbide. These substances, when maintainedji 

 a sufficient temperature, behave exactl^^H 

 aqueous solutions of certain compou 

 which we can precipitate or displace t In* or that 

 substance present in solution or combimr 



Writing, in the " Ir f the fat;. 



metals. 1'. Kn-uzpointm-r mention* the factor of 

 the ability of a oeam, axle, tire, or stamp stem 



ndu'et vibrations speedily awny fr 

 point of impact and distribute the rootU 

 thus caused uniformly and uninterrupted! 

 point to point a verv important el- 

 strength and durability of a Mru<" 

 often ignored or pa -ed overhaul. 

 metal a known good conductor of L 

 that, other things being ejunl. 

 can be impaired in various ways by fl 

 purities, hollow space- 

 want of uniform density, and others. Ti 

 impinging against the metal not b 

 conducted away on account of one of th 

 pediments, the metal at or near the point t 

 contact with the fire becomes hotter than it 

 would if conductivity was unimpaired. The 



