414 THE SCIENTIFIC PAPERS OF 



why he did not persevere with the basic lining was, that although 

 for a few charges it seemed to stand exceedingly well, the slag 

 containing silica and oxide of iron acted upon it more rapidly than 

 was desirable ; and it was subject, moreover, to the inconvenience 

 that, unlike a silica lining, it could not be repaired. In dealing 

 with silica they had only to put in a few shovelfuls of sand where 

 the lining was defective, and after the application of heat for a few 

 minutes, the new material was found to have perfectly combined 

 with the old ; whereas with a basic lining, the lining had to be 

 taken out when defective and entirely renewed. These results 

 discouraged him from continuing the application of these linings 

 to the open-hearth furnace. He still continued, however, the use 

 of bauxite brick lining in his rotative furnace, in the manner 

 described in his paper before the Iron and Steel Institute in 1873. 

 Reference to the same subject would also be found in his printed 

 lecture, delivered to the Fellows of the Chemical Society in 1868. 

 With regard to the subject now brought before them, he found 

 that there was something wanting in the papers communicated. 

 Mr. Thomas, in his paper, stated that the amount of basic material 

 added usually exceeded 2 cwt. per ton of pig iron. He wished 

 Mr. Thomas had given them, not what it exceeded, but the exact 

 amount. They knew that basic material would absorb phosphorus, 

 but the President in his able address had already called attention 

 to the circle through which they seemed always to wander in 

 developing the different processes for the manufacture of iron and 

 steel. The puddling furnace had originally a silica lining, and 

 only after a basic lining had been adopted were good results 

 obtained. It was probable, therefore, that in making steel they 

 were only now passing from the first stage to the second. The 

 difficulty they had to contend with in this case was, however, a 

 more serious one, inasmuch as the temperature was very much 

 higher than in the puddling furnace, in which the oxide lining 

 could be as easily maintained as the silica lining that was 

 previously employed ; but it was to be apprehended that the use 

 of a basic lining in the Bessemer converter and in the open-hearth 

 furnace would entail a good deal of difficulty and expense in the 

 renewal of the lining on which subject, however, he should 

 be glad to elicit more definite information from the authors of the 

 paper. 



