154 



THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. 



[Mat, 



new system of producing iron in its malleable state (without the intervention 

 of the previous process of smelting) direct from the puddling furnace. 

 Taking them in tlieir separate order, the first vcill be — 



Smelting. — As the infusion of carbon, and the consequent expulsion of 

 tlie excess of oxygen from the rich ores, may be considered a necessary, as 

 well as a preliminary process, it is oiivious, that the plan of stirring and 

 roasting in a separate furnace, as adopted by Mr. Clay, is both tedious and 

 expensive ; and now that he is engaged by the Turkish Government, for the 

 purpose of carrying out a more complete and comprehensive system of manu- 

 facture, it appears worthy of the skill and consideration of the chemist and 

 metallurgist to cheapen the process, and, if possible, to effect the deoxida- 

 tion of the ores by one direct operation on the top of the furnace. If the 

 ores can be deprived of their oxygen in this way, by alternate layers of char- 

 coal and coke, there scarcely exists a doubt, but that the finer particles of the 

 pulverized ores, will receive their proportionate dose of carbon, previously to 

 their descent to the point of fusion in the furnace. 



In the preparations for smelting, the past experience of Mr. Ilcath, and 

 the knowledge of his treatment of similar ores at the works of Porto Nuovo, 

 insure great certainty in the operations under consideration. It is probable 

 that the simple method of moistening the ores with water might answer 

 every purpose of cementation, and by the introduction of the hot blast, the 

 whole process of deoxidation and fusion might be cfTected in the furnace at 

 one and the same time, without the intervention of a separate system of 

 preparation. It is understood, that Mr. Heath adopted this method with 

 complete success at Porto Nuovo, ami provided it can be accomplished in 

 the instance of the Samakoff and Ulverstone ores, it will effect a considerable 

 saving in time, labour, and expense. Should it, however, not succeed, there 

 is still in reserve the preparatory process in a separate heating furnace, as 

 adopted by Mr. Clay. But a few trials of the carbonizing ell'ects of the hot 

 blast on the top of the furnace, will determine these matters, and will 

 shortly point out the most direct and most economical process of carburation. 



As respects the dimensions of the furnace to be used, it is decided to make 

 it 40 feet high, 9 feet diameter at the boshes, and 4 feet diameter with a 

 height of 6 feet C inches in the hearth. This will be looked upon as a small 

 furnace, when compared with those used in this country for reducing the 

 leaner ores ; but when it is considered that the nature of the materials is dif- 

 ferent, and that charcoal with a slight admixture of lignite will be used, 

 instead of raw coal and coke, it is probably of the best proportions that could 

 be adopted for such a purpose. The small furnace has, in every instance, 

 been used by Mr. Heath at Porto Nuovo, and the same description of char- 

 coal furnace is now in operation under the direction of Mr. Roper at Back- 

 barrow, near Ulverstone. 



Puddling. — For the conversion of such iron ores, as the Ulverstone, and 

 those of Samakoff, into the malleable state, it would appear, that Mr. Clay's 

 new process is the cheapest, and probably the most efficient, that can be 

 employed. On the old plan, when a superior quality of wrought iron is re- 

 quired, a long series of consecutive operations is necessary, and as these ope- 

 rations are both tedious and expensive, it becomes desirable to dispense with 

 the process of the ponderous blast furnace, and to encourage the more direct 

 action of the puddling process, as pursued by Mr. Clay. In the description 

 given to the Institution of Civil Engineers on a former occasion, the opera- 

 tions of the old plan are stated to be : — 



1st. Sraelting in the blast furnace. 

 2nd. Iletiiiing. 



aid. Puddling, hammering and rolling 

 4th. Cutting up, piling and rolling, 

 ^th. Cutting up, piling and rolling. 



All these processes require a separate applicatioirof [lieat. — On the uew 

 plan, the operations are reduced to two, viz. : — 



1st. Puddling, hammering and rolling. 

 2nd. Cutting up, piling and rolling. 



This latter process, according to the author, brings out the iron superior 

 in quality to the fifth operation of the old system, and with the advantages 

 of saving a considerable portion of time, and a great quantity of fuel. The 

 manufacture of this description of iron, direct from the ore, appears to be 

 simple and effective. The requisite preparations would be four or six pud- 

 dling furnaces attached to the rolling mill, and v;ith a proper mixture of 

 ground charcoal, the charges might be puddled and worked ort' at a compa- 

 ratively low rate. After the balls or blooms are formed, they are brought 

 under the hammer, and from thence to the rolls, where they are formed into 

 rough bars j these bars are then cut up into lengths, and piled or shingled ; 

 after whicli they are again heated, hammered, and rolled into finished bars, 

 and being cut at the end and straightened are ready for the market. 



This appears to be the whole of Mr. Clay's process, except the pounding 

 and cleansing of the ores, which require care and attention, previous to the 

 mixing with the coal or coke. 



In the Samakoff ore, the necessity of cleansing for this process will, it ap- 

 pears, be indispensable, as the silica will require to be removed, and the ore 

 cleaned from impurities, before it is mixed with the ground charcoal ; this is, 

 however, a simple process, which is easily accomplished by the means already 

 described. 



During the experiments, for ascertaining the best and most effectual means 

 for reducing the ores of Samakofi', frequent opportunities offered, for a simi- 

 lar inquiry relative to the ores of other districts, and amongst others, those 

 of Lancashire and Cumberland. To these inquiries every attention was paid. 



and now, that an opportunity occurs for investigation, it may be useful in 

 determining the transverse strength of the Turkish irons, to include those 

 not before experimented upon, and to compare them with other experiments 

 of the same kind, made some years since upon nearly the whole of the 

 British irons. These experiments have been published in the 6tb volume of 

 the new series of the " Memoirs of the Literary and Philosophical Society of 

 Manchester." and in order to render the general table of practical value, the 

 more important parts of all the tables annexed to the paper* have been in- 

 serted, not only for the sake of comparison, but for practical purposes, in 

 supplying the means of selecting such irons as may be required for the varied 

 objects of architectural, as well as engineering construction. These tables 

 have occasionally been found of great value, and the addition of new and 

 richer irons will add to their utility, and remove all doubt, as to the selection 

 of qualities necessary to be employed, for different mixtures in the arts. 



STRENGTH OF CAST IRON BARS. 

 Table of Results, obtained from Experiments on the Strength and other Pro- 

 perties of Cast Iron, from the principal Iron Works in the United Kingdom, 

 with the addition of those of Elba and of Samakoff (Turkey.) 



Abbreviation— C. B. cold blaat.— H. B. hot blast. 

 la the following Table, each bar la reduced to e-vaclly one inch square; and the trans- 

 verse strength, which may be taken as a criterion of the value of each iron, Is obtained 

 from a mean between the experlmehts upon it, — first on bars 4 feet 6 inches between the 

 supports, and next on those of half the length, or 2 feet 3 inches between the supports. 

 All the other results are deduced from the bars 4 feet 6 inches long, which have not been 

 introduced into the Table. In all cases the weights wera laid on the middle of the bar. 



The irons with asterisks are taken from the experiments on hot and cold blast iron 

 made some years since by Mr. Hodgkiusou and Mr. Fairbairn, for the ** British Associa- 

 tion tor the Advancement of Science." — See Seventh Report, vol. vi. 



The modulus of electric'ty was usually calculated from the deflexion caused by 112 lb. 

 on the bars 4 feet 6 inches long. 



The experiments were conducted under the superintendence of Mr. Eaton 

 Hodgkinson, F.R.S., and in them, as well as in the others, he had especial 

 reference to the decrease of elasticity, in verification of the law of defective 

 elasticity, which was announced by him, to the last meeting of the " British 

 Association for the Advancement of Science," at Cork. In the experiments. 



* These tables are loo voluminous to he published in the Minutes of Proceadlngi, but 

 the results are given In the annexed table. 



