May 17, 1883] 



NA TURE 



69 



increased production of Bessemer and Siemens steel, the great 

 diminution in their price, the immense increase in shipbuilding, 

 the proposed improvements in the patent law, and the better re- 

 lations now existing between masters and workmen. At the 

 conclusion of his address the president presented the Bessemer 

 medal to Mr. J. G. Snelus of Workington for his achievements 

 in introducing the basic system for the making of steel. A 

 similar medal, bestowed upon Mr. S. G. Thomas, was reserved 

 until his return to England. 



The meeting then took up the discussion on a paper by Mr. 

 Snelus on the Chemical composition and testing of steel rail-. 

 This paper was read at the Vienna meeting of the Institute and 

 its discussion pi stponed. Mr. Snelus now added particulars of 

 a new test for the haidness of rails, which consisted in driving a 

 uniform punch under uniform pressure into a piece of the rail, 

 and measuring the depth of the hole produced. Various experi- 

 ments had satisfied him that this depth would be inversely pro- 

 portional to the hardness of the rail. M. Gaze's, engineer to the 

 Lyons Railway, read a very long note in French on the same 

 subject, the point of which was that, as he maintained, the 

 wearing power of the rail depends not only on its chemical 

 composition but also on the temperature in rolling and the 

 amount of compression which it has experienced while being 

 rolled. He stated that a percentage of carbon varying from \ 

 to I per cent, was found in France to give the best result for 

 rail heads. 



Two papers were then taken together : the fir>t of these was 

 by Mr. Wm. Parker (Chief Engineer and Surveyor of Lloyd's), 

 on the Use of steel castings in lieu of steel and iron forgings for 

 ship and marine engine construction. This paper gave the 

 results of an important investigation made by Lloyd's Registry 

 into the applicability of steel castings to heavy articles such as 

 crank shafts, sternposts, &c, which had hitherto been chiefly 

 made in forged iron. The result was to convince the Committee 

 that such conductions can be made of cast steel quite as good 

 for the purposes intended as those of wrought iron, and without 

 the uncertainty which always exists more or less in large iron 

 forgings. The making of such castings is mainly in the hands 

 of three firms, who, however, differed very materially in their 

 views of the best mode of proceeding, especially as to whether 

 the metal should be melted in crucibles or in the ordinary open 

 hearth. At Terre Noire, where such castings are also made, 

 great importance is attached not only to annealing but also to 

 tempering them in oil ; and the author gave particulars of ex- 

 periments made on this subject, which showed that such treat- 

 ment had a marked effect in increasing the strength of the 

 specimens whilst slightly diminishing their ductility. Reference 

 was made to the distinction between forged steel and cast steel, 

 and a number of experiments were quoted on similar bars of 

 both these materials and also of wrought iron. In these experi- 

 ments the strength of the cast steel specimens was in every case 

 greater than those of the wrought iron, whilst the ductility was 

 about the same. With the forged steel the tensile strength was 

 designedly made low, but the ductility was very high. Taking 

 the product of the ultimate strength and ultimate elongation as 

 representing roughly the quality of the material, it appears that 

 the cast steel is one-third higher than wrought iron on an 

 average, whilst the forged steel is three times as high. Trans- 

 verse tests, both by steady pressure and by impact, and also 

 torsion tests, gave results practically similar. I- ii ally some 

 experiments made by Mr. James Neilson on steel, partly as cut 

 from the ingot and partly as hammered or rolled down to a 

 comparatively small thickness, showed that the latter process 

 produced a very decided increase both as to strength and duc- 

 tility in some cases, although the results were not very uniform. 

 For casting crank shafts and similar work Lloyd's Committee 

 considered that the tensile strength of the steel should not exceed 

 thirty tons per square inch, and that a piece \\ inch square 

 should bend cold through an angle of 90 degrees. 



The second paper was by Mr. Wm. D. Allen, cf Henry 

 Bessemer and Co., and was on Bessemer steel in its cast and 

 unwrought state. The object of this paper was to dispel the 

 idea that Bessemer steel is not a safe material for casting on 

 account of the frequent presence of cavities or blowholes within 

 it. From daily experience Mr. Allen affirms that perfectly 

 sound castings can be made from Bessemer steel, provided that 

 the ladleful is alloyed either with ferrouianganese or with some 

 iron ore rich in silicon. In order that this alloy may mingle 

 perfectly with the steel, the ladle should be violently stirred by 

 means of an agitator, already described to the Institute. Of such 



steel, the reader stated that neaily 500 hydraulic cylinders had 

 been made, and tested up to two, three, or even four tons per 

 square inch. 



An interesting discussion followed these papers. Mr. James 

 Riley doubted whether the crucible process produced a result 

 more uniform than the open hearth, and spoke strongly in favour 

 of annealing and tempering in oil. He also doubted whether the 

 work put upon forged steel gives the advantage which was 

 claimed for it. Mr. Hall (Messrs. Jessopand Sons, of Sheffield) 

 defended the crucible process, but di-paraged Bessemer castings. 

 Sir Henry Bessemer, however, considered that the agitator had 

 overcome the difficulty which previously existed in making 

 s >und castings in his steel, while Sir Wm. Siemens observed on 

 the danger that castings may contract unequally in cooling, 

 and on its complete cure by annealing. He suggested on 

 explanation for the curious fact of the advantage due to oil- 

 hardeniwg, namely, that the oil produced a compression of the 

 outer layers, « hich acted on the rest of the mass, and was of more 

 effect than any mechanical pressure could he. 



The second day's proceedings opened with the reading of two 

 papers on the vexed question of hot blasts and high furnaces. 

 The first was by Mr. Wm. Hawdon, who gave the particulars 

 of comparative experiments made on one of Messrs. Samuelson's 

 furnaces at Middlesborough, which had been supplied alternately 

 with blast from pipe stoves at 990° F. and with blast from fire- 

 brick stoves at 1400 F. The final result was an increase in the 

 make per week from 400 to 458 tons of pig, a diminution in the 

 coke per ton from 23 '8 to 22 '3 cwt. , and at the same time an im- 

 provement in the quality of experiments at the various tempera- 

 tures of blast between these two limits showed a gradual rate of im- 

 provement. At the same time the tem| erature of the escaping 

 gases was diminished from 468 to 44S°, and the volume, of 

 course, was diminished also. Comparing the two modes of heat, 

 he showed that the area of heating surface in proportion to the 

 cu'nic capacity of the stove was much greater in the firebrick 

 than in the pipe stove, giving a corresponding improvement in 

 effect, and that the gases escaping from the chimney, which in 

 the pipe stoves had a temperature of 1240 F., in the brick 

 stoves were as low as 250° F. The result was to effect a very 

 considerable saving of gas used for heating the Mast, which gas 

 may, of course, be utilised for steam-raising or other purposes. 



The second paper was by Mr. I. Lowthian Bell, F.R.S., and 

 dealt with the Value of successive additions to the temperature of 

 air used in smelting iron. This paper was to some extent a 

 rejoinder to these of Mr. Charles Cochrane, recently read 

 before the Institution of Mechanical Engineers. Mr. Bell first 

 considered the proposed application of hydrogen, or what is 

 called water gas, to the bla-t furnace, and showed that this 

 could produce no advantage in saving of heat. He then dealt 

 with the question of the possible economy of coke in an 

 ordinary furnace, and reiterated that a limit was placed to 

 such economy by the fact that when the escaping gas 

 consists of carbonic oxide and carbonic acid in the propor- 

 tion of 2 to 1, these combined gases can no longer pro- 

 duce any effect in reducing iron ore. Hence the very great 

 saving of fuel which had at first been effected by enlarging the 

 size of the furnaces and increasing the heat of the blast, had 

 now nearly reached its limit ; which Mr. Bell still held to 1 e 

 represented by a capacity of about 15,000 cubic feet, and a tem- 

 perature of about 1000° F. He dealt with the suggestion that 

 the heating of the blast could be advantageously used to replace 

 the heat evolved in burning carbonic oxide and carbonic acid j 

 and showed that to effect any great improvement in this particular 

 would require blasts of too high temperature to be practically 

 available. He commented upon the results with the furnace at 

 Messrs. Samuelson's works, and considered that the increase in 

 the make must be due to the increased quantity of blast rather 

 than to its higher temperature. He admitted a saving in coke 

 of about I cwt., but he observed that on the o'her hand the 

 furnace was driven very slowly, only supplying about half the 

 weight of pig iron per cubic foot of capacity which was usually 

 supplied by the furnaces in the Cleveland district. 



Mr. Bell's posiiion was strongly assailed by Mr. Charles 

 Cochrane ; but although the questions between them were still 

 further debated, it can hardly be said that they are completely 

 settled. The problem is one which involves several independent 

 factors, and a variation in any one of these might produce a large 

 effect on the final result. It was so far fortunate that on this 

 occasion the question of stoves and of blast furnaces was con- 

 sidered together, and not separately, as is often the case ; but 



