SEGREGATION AT FURNACE AND FOUNDRY.
increase of silicon in the metal from the bottom upwards as it lies in a furnace before being- tapped.
Variations in the working of a furnace make a radical difference in diffusion of the metalloids silicon and sulphur, as can be seen by the following analyses, which the writer has also secured for this work through the courtesy of Mr. C. C. Jones, an able, experienced furnace manager, operating two furnaces at Sharps-ville, Pa. The pig beds are numbered in the following Table 19 according as they were cast, No. i being that farthest from the furnace, receiving the first iron and No. 6 the last:
TABLE IQ.—ANALYSES OF PIG BEDS IN A CHANGEABLE FURNACE.
i 2 3 4 5 6
60 68 7O I OO I 2^ 2 2O
Sulphur .................................. .084 071 ./u 062 050 .OA2 O27
Witli the furnace normal the result was as follows:
2 18 2 l8 2 22 2.23 2.25 2 25
Sulphur ............ 02 1 021 O2 ) OIQ .019 .019
The above analyses of the normal working of a furnace present the best uniform distribution of silicon and sulphur which has come under the writer's notice. As this is a question of no little importance to the founder, attention is called to Table No. 20, on next page, showing the analyses of eight (8) different "casts'* giving the silicon contents from the bottom upward, subscribed by Mr. H. Rubricius in Chemiken Zeitung and the Journal of the Iron and Steel Institute, No. 2, 1894.
The exhibits treat only of silicon and sulphur. With regard to the segregation, etc., of phosphorus and manganese, the only experiments which the writer has observed are those by Mr. A. P. Bjerregaard, com-therwise. Largely for '