California Paper - The Temperatures at which Certain Ferrous and Calcic Silicates are Formed in Fusion, and the Effect upon these Temperatures of the Presence of Certain Metallic Oxides

In the blast-furnace smelting of lead, copper and other non-ferrous metals, the largest part of the product obtained is slag. Its formation consumes more of the heat-energy of the fuel charged than any other chemical reaction that takes place. It is therefore of importance to know at what temperatures the different slags will form, so as to be able to choose in a given case the slag that will form at the right point in the operation, will keep the products thoroughly fluid, so as to insure a satisfactory separation, and will permit the consumption of fuel to be reduced to the lowest practicable point. While practical experience has brought out in a general way the leading differences as to the formation-temperatures of Rome silica—iron —lime slags, accurate details are still wanting. The object of the investigation here described was to supply some of these.* Prominent among the men who have worked on the fusibility of silicates are Lampadius, † Sefström,‡ Berthier,§