Illustrations— 1. REOPENING THE TILLY FOSTER MINE, NEAR BREWSTER’S, N.Y.
                        2. ENGINES, AIR COMPRESSORS, AND HOISTING PLANT

For nearly two years past a most interesting piece of engineering work has been progressing in the reopening of the Tilly Foster iron mine, near Brewster’s Station, Putnam County, about fifty miles from New York City on the line of the New York and Harlem Railroad. The mine is owned by the Lackawanna Iron and Coal Company, and its ores have long been considered very valuable, having been principally used at Scranton and Bethlehem, Pa, in the production of Bessemer pig. The expense of getting out the ore, however, has been great, owing to the irregular and nearly vertical overlying strata, and the production has steadily declined, the stratification necessitating the leaving of large quantities of ore in position in the pillars and roofs. An attempt was made to use concrete pillars, but these artificial supports were found to be too liable to crush and their use was abandoned. All other plans having failed, it was finally determined to adopt the bold scheme represented in our illustration which is nothing less than the entire removal of the whole of the overhanging rock, thus making the mine an open cut. The work was commenced in June, 1887, and up to March of this year 230,000 cubic yards of material had been removed. The excavation is now about 450 feet long, 300 feet wide at the widest part on top, and 170 feet deep. Of the material thus far taken out, there have been some 15,000 cubic yards of rock in which ore was mixed The total contemplated rock excavation amounts to 350,000 cubic yards, in order to secure an estimated quantity of 1,000,000 tons of ore. The contract price for the rock excavation was $1.15 per cubic yard, the taking out of the ore and separating it from the rock being paid for at a higher figure. One thousand tons of material are handled every ten hours, through the aid of a series of wires stretched across the pit.