take the balance if we would take a small patent flour-mill at $125 in pay, which Mr. Campbell did. He shipped it here. We tried it, but it was no good, and we sold it to a man in the mountains for $30; and thus ended our coke business.' These gentlemen lost heavily in their venture. It was not until the Baltimore and Ohio Railroad was completed to Pittsburg, and Connellsville coke had been used successfully in the Clinton Furnace of Graff, Bennett & Co., at Pittsburg, that its value as a furnace fuel was thoroughly demonstrated and the foundation laid for the demand that has resulted in such a development of the coke manufacture in the Connellsville region. This furnace was blown in, in the fall of 1859. The coke was at first made from Pittsburg coal, near the furnace on the south side of the Monongahela River, nearly opposite the Point, at Pittsburg. The furnace was run for about three months, when, the coke made in this way not proving satisfactory, it was blown out, and arrangements made to secure a supply from the Connellsville region. The furnace blew in again early in the spring of 1860, the coke used being from the Fayette Coke-works on the Baltimore and Ohio Railroad, made at first on the ground in pits. The result was so satisfactory that thirty ovens were built in 1860, and arrangements were made to secure a continued supply."
The general tendency toward improvement in all branches of manufacturing that began to manifest itself in America about the year 1840, and which, fortunately for the welfare of the country, has grown with the years and strengthened with each new triumph of inventive thought, prompted investigation with a view to determine what constructive ideas were really essential to the building of a thoroughly efficient blast-furnace in which coke was to be used as the fuel; and it was very soon ascertained that European metallurgical engineers had discovered that it was not at all necessary to purchase a stone quarry before commencing the erection of a furnace, and that all the functions of successful smelting could be performed in a structure consisting substantially of a sheet-iron casing lined with fire-brick, supported upon cast-iron columns, between which were the tuyères and dam, which were thus rendered readily accessible; the furnace being entirely unincumbered with ponderous masses of supporting masonry. This form of furnace was not a creation, but the result of a gradual evolution from the old truncated pyramidal structure whose massive proportions were ignorantly supposed to be absolutely necessary, not only to support the weight of ore and fuel, but also to confine the heat in the furnace. The first deviation from the old construction consisted in a reduction of the quantity of material used by making all that part of the furnace above the tuyère arches either cylindrical or conical, and binding it with iron