3S 



NA TURE 



[May io, 1894 



naiurally nit •>« so continuou-i as in the case oT an establishment 

 devoted entirely to ihe production of steel castings. It may be 

 stated that the price of sieel as it stands in the ladle is given as 

 4s. 6d. t)er cwt., whilst the cos" of a complete installation of 

 moderate siz' would be aHout ;£^35O0. In calculating the cost 

 of the steel in the ladle, the author appears to leave out Ihe 

 fixed expenses. It is doubtless a tempting thing to the managers 

 of engineering workshons to have their own steel foundry, 

 especially as it is ofien difficult to obtain castings with prompt- 

 ness and punctuality, the aHvantage of producing all pans 

 required at home, and thus having control of delivery, is apparent. 

 It is very easy, however, to carry this principle too lar. The 

 time of a works manager is limited, and without the master's 

 eye there is likely to be much leakage in a department. Manu- 

 facturing establishments may be tooselfcontained, and there are 

 many unfortunate instances of works producing everything 

 required, excepting dividends. 



A short discussion followed the reading of this paper, those who 

 spoke being altogether favourable to the process. Unfortunately 

 the large number of papers that were on the list made the President 

 fearful that the whole programme would not he carried through 

 in the two days, and he therefore closed this first discussion very 

 abruptly. Had he not done so we believe that the discussion 

 would not have been throughout of so flattering a description. 



The next paper read was a contribution by Mr. Jeremiah 

 Head, entitled " Scandinavia as a Source of Iron Ore Supply." 

 Mr. Head has recently made a tour through Norway and Sweden, 

 going toihe extrsmcnorthof the Scandinavian Peninsula, and in 

 his paper he discussed the iron-producing capabilities of these 

 countries, of which he appears to take a somewhat sanguine 

 view. He pointed out that in the case of export duly being 

 placed on iron ore by the Spanish Government, the steel 

 makers of this country might be put in an awkward position, 

 depending as they did so largely on Bilbao ore. Some of the 

 experienced sleel makers present, however, by no means agreed 

 with Mr. Head in his estimate of the value of Scandinavian 

 ore. It would appear that until a railway is constructed to the 

 Norwegian coast, which, unlike the Haltic, is free from ice at 

 all times of Ihe year, there is not much prospect of a continuous 

 supply of ore being obtained Irom northern Scandinavia. The 

 objection that for half a year there is almost continu.il night in 

 this district, was, Mr. Head said, an im.iginary one, the fact 

 being that the Scandinavians carry on their business all through 

 the year without trouble. The brilliant moonlight, the 

 Northern Lights, and the twilight that exists, aided by the 

 reflection from the snow-covered country, enables work to be 

 transacted. Mr. Head's paper contained a great deal of useful 

 information on the subject, analyses of the ores being given, and 

 figures as to the cost, &c. 



On the second day of the meeting the proceedings were 

 opened with a paper by Mr. William Ilawdon, on "The 

 Capacity and Form of Blast Furnace>." The author com- 

 menced with some interesting figures on the increase in capacity 

 of blast furnaces ; in Cleveland durin; recent years the content 

 has risen from about 6,000 cubic feet to as much as 30,000 cubic 

 feet, with the result of increased economy and larger output. 

 In discussing the proportions of furnaces, he pointed out that 

 the crucible or well of the furnace, that is the part immediately 

 above the hearth, has its diameter governed by two considera- 

 tions : if it be too larj;e, a pillar of perfectly cold material may 

 be formed in the centre of the massol ore, fuel, &c., contained in 

 the furnace ; whilst if the diameter were 100 small, there would 

 not be .sufficient space to give the required volume for combus- 

 tion in order to obtain a given output. 'Ihe melting zone above 

 the crucible must also be designed so as to allow an easy pene- 

 tration of the blast through Ihe materials. When air is blown 

 into a furnace it has to be expanded by the expenditure of heal, 

 but if air be introduced at a high temperature and already in an 

 expanded stale, a mnre rapid combustion is obtained «ilh a 

 ■aving of fuel in the furnace. In the case of cold blast being 

 used, inlcnsily of combustion does not spread over a large space, 

 and therefore a smaller well suffices. High temperature of 

 blast require* a larger area in ihe neighbourhood of the tuyeres, 

 through which it is admitted, ll is necessary that the furnace 

 materials should come down from the upper reaches thoroughly 

 heated and reduced, and in as level a manner ,as possible over 

 the entile area. In order Io obtain capacity and to support the 

 material, and also to prevent loo dense packing near the tuyeres 

 at (be lone of fusion, the blast furnace is made with boshes ; 

 thai 15 to say, the interior space enlarges suddenly, Ihc walls 



NO. 1280, VOL. 50] 



taking a slope of 60" to 80", the angle of repose for diy 

 materials being about 45°. But when the minerals become 

 plastic, the angle of the bosh requires to be more steep. Above 

 the slope of the boshes there is the maximum diameter of the 

 barrel of the furnace. When, owing to ihe relative sizes of the 

 wall and the barrel the bosh occupies a large vertical space, 

 thus retiring a long way hack, the materials at the sides are loo 

 far removed from the ascending current of gas, and will come 

 down in a |ierfecily raw stale. The author gave an amusing 

 example of this error in furnace construction. In one case, 

 after a few months' working it was discovered that some wooden 

 sleepers that were originally placed in Io light up the furnace, 

 had not been consumed, and were in fact found only charred on 

 the surface, re>ling near the top of the bosh of ihe furnace. Id 

 order loget overlhe somewhat conflicting conditions we have here 

 referredto, Mr. Hawdon and his friend Mr. Ilowson had designed 

 a furnace of comparatively narrow dimensions, but enlarged at 

 the upper part, thus giving, as it were, a second bosh. In this 

 way in the higher region where the charge is in a dry and porous 

 slate and not subject to extreme pressure, capacity is obtained, 

 whilst Ihe direct weight upon the lower porlions ol ihe materials 

 is reduced. With a furnace of this nature, which has been in 

 work some short time at the Newport Iron Works, the author 

 obtained in smelling hematite a fuel econoiry of 15 cwts. of 

 fixed carbon per ton of iron, the weekly output being 932 tons, 

 the ore being 50 per cent. One great advantage in the use of 

 this form of furnace would appear to be regularity of the pro- 

 duct, freedom being obtained from that uncertain recurrence of 

 white iron which is so often a trouble to Ihe blast furnace 

 manager. It should be remembered that the furnace h.id not 

 been in work for any considerable time, and new furnaces nearly 

 always work better than when they have betn in blast a few 

 years. On the whole, however, it would seem that Mr. Hawdon 

 has made out a very good case for his new firm of furnace, and 

 indeed the promises are so good that doubtless many more will 

 be erected on these lines. 



The remaining paper read at Ihe meeting was by Prof. J. O. 

 Arnold, of ShelTieKl, and was entitled "The Physical Influence 

 of Elements on Iron." We approach this paper with despair. 

 In the first place, it was one of extreme length and is full of 

 facts from cover to cover. In the second place, the discussion 

 which followed its reading was of such a nature ihat many of 

 the speeches which had been prepared beforehand, and were 

 read by their authors, were really of the nature of papers in 

 themselves. Indeed one speaker, Mr. Iladfield, of Sheffield, 

 had prepared a paper of some length which had been called 

 forth by Mr. Ainold's monograph, and extracts from ihis were 

 read by the author during the discussion. M. Osmond, Prof. 

 Roberts-Austen, Sir Lothian Hell, and Mr. Gowland had 

 also prepared what in effect were scpaiale monographs 

 on the subject ; whilst Mr. Sle.id, of Middlesbotough, 

 spoke at considerable length. In addition Io these there 

 were several other speakers. We could not abstract Prof. 

 Arnold's paper in anything approaching the space we have at 

 our disposal here, important and interesting as the subject is ; 

 and even could we do so, it would be hardly fair to those who 

 look opposite views to him, as we cannot reproduce their argu- 

 ments. Under these ciicumslances we must content ourselves with 

 giving the very briefest idea of the subject, referring our readers 

 to Ihe 7 ransaclwin oi the Institute for lull information, ll will 

 be remembered that at a meeting of Ihc Insiitute of Mechanical 

 lingineers. Prof. Arnold made a very strong ati.ack upon 

 Ihe report presented by Prof Koberls-Austen as chairman ol the 

 Alloys Research Committee of that Insliiution. Prof. Koberls- 

 Auslen in his report adopted ihe theories brought forward by 

 M. Osmond in regard 10 ihe critical points, or evoUuions of 

 heal during the cooling of mild steel, (loin a temperature "f 

 l<X)0" C. These critical points were : — firstly, the sligh 

 evolution of heal at 850" C. This point is known as .\i 

 Secondly, a faint disengagement of heat at atxiut 750' C, lli' 

 point Arj, the third point Ar,, is at about 650 ; the latter 1 

 almost absent in very mild steel, but becomes highly accentuated 

 In steels high in carbon, and was therefore due to a combination 

 of iron and carbon to form the definite carbide I'e, C. M. 

 Osmimd maintained, what I'rof. Arnold designated the "start- 

 ling theory," thai the poinl Ar, marked Ihc vital change of ihc 

 passage into ordinary soft iron of an allolropic modification of 

 iron (existing at temperatures above the ciilical point) of ada- 

 mantine hardness. This allolropic form M. Osmond named 

 5 iron Io distinguish it from o or soft iron. He fuither staled 



