M I. I M.I.I BOY. (MlHCKLLANBOUS.) 



from li ti> ti , while tin- hydrochloric 



condensed mid is used over again in the 

 galxani/.in:,' proci-s-. When the a|i|iaratiis is once 

 i ami in working order, il i> only neces- 

 sar\ io supply il with fuel in order to rcco\er 

 hydrochloric acid continually from waste pickle, 

 and to remove i ho irregularities in the form of 

 oxide of iron. The acid reco\eivd is generally of 

 the -aine strength as that originally used for 

 pickling, ami is suitable for use in galvanizing. 

 \ide of iron is used for filtering in the 

 puddling procc-s and for other purposes for 

 which it i> well adapted, and pies a long way 

 toward paying for the fuel that is used. 



The experiment of glazing a furnace lining 

 \\-i- successfully tried at the Crown Point Iron 

 Company's works. Lake Cliamplain. on the oc- 

 i.ni of relining and starling in blast one of its 

 rge furnace-. After the lirc-l .ricks were in place 

 cheap article of graphite or plumbago was re- 

 uced to a paste with water, and the interior of 

 the furnace washed with it. The plumbago paste 

 a slippery glaze to the fire-brick lining, 

 which refused to be coated with slag, and the 

 pressed down in less time and left the 

 _ free and clear. 



In the new method for producing steel free 

 (torn sulphur and phosphorus proposed by the 

 'Vnch Societe Metallurgique du Midi, the pig 

 on is taken at the moment of fusion, and, some 

 minutes before introducing it into the converter, 

 very fine sand and a very small quantity of crys- 

 talli/ed chromic acid are thrown into the bath. 

 fter introduction into the converter, as soon as 

 ption begins, finely divided carbonate of am- 

 onia, inclosed in small balls of pure pig, is in- 

 "uced into the bath. The product of the cast- 

 is a homogeneous iron or steel, free from 

 etalloids. 



The method of M. Bertrand, of Paris Grenelle, 

 'or producing magnetic oxide on iron consists 

 sent ially in depositing by galvano-plastic means 

 metal or a metallic alloy susceptible of vola- 

 tilization at a temperature of about 1,000 C. 

 \fter receiving this coating the articles are in- 

 luced into a furnace, where the metallic de- 

 sit is volatilized. The iron oxidizes, without 

 giving sufficient oxygen to form a sesquioxide, 

 3ut enough to form the magnetic oxide. 

 Dr. W. Stahl's process for recovering cobalt 

 am low-grade ores consists in roasting the pow- 

 lered ore with salt and pyrites, whereby the 

 sbalt and copper and manganese, if present, are 

 >n\erted into chlorides, while the iron is chlo- 

 idi/ed to a small extent only. After roasting, 

 ore is leached with water, and the solution 

 treated with sulphuretted hydrogen to remove 

 the copper. From the filtrate cobalt is precipi- 

 tated with sodium sulphide. 

 Miscellaneous. With good reason, said Dr. 

 Tedding, of Germany, in an address before the 

 Iron and Steel Institute, may the invention of 

 the Brothers Mannesmann in the manufacture 

 of pipes be regarded as an important improve- 

 ment. For pipes destined to meet severe re- 

 quirements of resistance to interior pressure, 

 it is indeed calculated to revolutionize pre- 

 vious practice. The process consists in feeding 

 a solid, highly heated round bar of ingot metal 

 between rolls which, while their axes are oblique 

 to the axis of revolution, revolve in the same 

 VOL. xxxi. 33 A 



direction. The metal of the surface of t 

 llnis acquires an inciea-ed motion m a -piral di- 

 rection, and is drawn over its core, m-i-iving, 

 eoiisi-i|ui.|illy. the. form of a pipe. It i> n,,t 

 praetienble, without an excessive expenditure of 

 power, to make the interior diameter of such a 

 pipe very large. But it is siiflicicrit that an in- 

 terior -pace i> created, for there j> no difficulty 

 in widening it over a mandril. Since in the 

 operation the pipe moves spirally forward and 

 all its parts are spirally pushed and pressed, the 

 metal becomes still denser. It is this -piral ar- 

 rangement of material which makes tlie Man- 

 iiesmann pipes so remarkable, apart from the 

 advantage they posses- in presenting no lines of 

 welding. Moreover, blow-holes are so squeezed 

 out spirally as to make the walls of the pipe 

 impermeable. 



The importance of extending the use of the 

 less-known metals is pointed out by Prof. \V. ( '. 

 Roberts-Austen. There will doubtless be in the 

 immediate future, he says, a rapid increase in 

 the number of metallurgical processes that de- 

 pend on reactions which are set up by submitting 

 chemical systems to electric stress. Sodium is 



growing in importance for cheapening the pro- 

 uction of aluminum, and as a powerful weapon 

 of research. The production of magnesium, 

 which was a curiosity a few years ago, now con- 

 stitutes a considerable industry. We may con- 

 fidently expect to see calcium and barium pro- 

 duced on a large scale as soon as their utility has 

 been demonstrated by research. Minerals con- 

 taining molvbdenum are not rare, and the metal 

 could probably be produced as cheaply as tin if 

 a use were to be found for it. The quantities of 

 vanadium and thallium that are available are also 

 far from inconsiderable ; but we as yet know lit- 

 tle of the action of any of these metals when 

 alloyed with others which are in daily use. The 

 field for investigation is vast indeed, for it must 

 be remembered that valuable qualities may be 

 conferred on a mass of metal by a very small 

 quantity of another element. The useful quali- 

 ties imparted to platinum by iridium are well 

 known. A small quantity of tellurium obliter- 

 ates the crystalline structure of bismuth, but 

 we have lost an ancient art which enabled brit- 

 tle antimony to be cast into useful vessels. Two 

 tenths per cent, of zirconium increases the 

 strength of gold enormously, while the same 

 amount of bismuth reduces the tenacity to a 

 very low point. Chromium, tungsten, cobalt, 

 titanium, cadmium, zirconium, and lithium are 

 already well known in the arts, and the valuable 

 properties which metallic chromium and tung- 

 sten cqnfer upon steel are already familiar: but 

 as isolated metals we know little of them. A rich 

 reward awaits the labors of chemist- who will 

 bring themselves to divert their attention, for 

 even a brief period, from the investigation of or- 

 ganic compounds to raise alloys from the obscur- 

 ity in which they -ire at present left. 



'In welding and metal working by elect rieity, 

 two systems are in use; the incandescent s\ 

 tern, m which the material operated upon is 

 traversed bv currents of large volume, and low 

 electro-motive force, the current having a con- 

 tinuous metallic circuit during the welding op- 

 eration ; and the arc system, in which the electric 

 arc is utilized. A pajx-r by Mr. A. B. Wood, in 



