president's address — SECTION B. 73 



ores, and both are treated on the spot into their respective marketable 

 products. In 1807 it occurred to M. Semennikow, then the govern- 

 mental head of the mining industry of the district, to have the question 

 of the suitability of copper mattes for the Bessemerising process looked 

 info, and accordingly a few preliminary trials, with small quantities, 

 ■were made at the Bogoslowsk copper plant, which were promising 

 enough to have him order their repetition with the paraphernalia of 

 the steel works at Wotkinsk near by. These tests were placed in the 

 hands of two officials, A. von Jossa and N. Laletin, who subsequently 

 published their results in the Russian Mininrj Gazetie of May, 1870.(^) 

 Honors are thus divided, M. Semennikow, as directive heod, carrying 

 the distinction of originator, the two subordinate engineers that of 

 executants of as interesting and important a set of technical investiga- 

 tions r-s — next to Bessemer's owti first trials — the world has ever seen 

 in this particular line of work. The investigations were most carefully 

 conducted, for that time, and the report is as creditable, painstaking, 

 and thoroughly scientific an one as the subject has yet been honored 

 with by any qualified metallurgist. It would take too long in this 

 place to go into all the details, but the following data are worth 

 presenting, to show how conscientiously and ably the work was 

 done. 



The principal tests at the Wotkinsk steel works were made on 

 rather small quantities, though no doubt these were considered very 

 liberal at the time, viz., a total of 500 pud (18,0001bs.) of matte, of a 

 grade of about 31.5 per cent, copper. Certain liberties of an experi- 

 mental character were taken with the converter blows, such as con- 

 tinuing the blowing beyond the critical points, the object being to gain 

 the information. The consequences, however, doubtless affected the 

 final verdict. The vessel used was of a somewhat antiquated t^^e, 

 ovoid in shape, flat-bottomed internally, with a height of 1.5 metres 

 and a greatest diameter of 1.25 metres, and with a long, retort-like neck. 

 It had seven tuyere bricks in the bottom, each with five openings, about 

 'fin. in size ; and in some of the tests, with air only, two additional 

 lateral tuyeres of Hin. diameter, lying tangentially in the plane of the 

 bottom, were brought into play, while, simultaneously, all the bottom 

 tuyeres were closed, except 6 to 10 of the holes. A number of tests 

 was made with steam and air, the former being introduced through 

 the centre bottom tuyeres. The matte was remelted in a gas-fired 

 reverberatory furnace, and run into the vessel in charges of 45 to 55 

 pud (l,6201bs. to l,9801bs.). The blast pressure ranged from 81bs. to 

 121bs. per square inch, but was manipulated to suit the phenomena, 

 the ejection of molten material from the nose giving rise to serious 

 apprehensions of loss, so that the experimenters strove to keep this 

 down by using only 41bs. to 51bs. pressure. The frequent choking of 

 the tuyeres also seemed ominous. It became necessary to clean them 

 as often as 10 times during a blow, and this appears to have been done 

 by interrupting the latter. The general run of the operation is, however, 



(l) Berg-u. Hnttenwdnn. Zeitg, 1871. The older files of this publication have 

 supplied a large proportion of the historical matter given in the paper. 



