Ore emerged from the ground mixed with sand and rock, and before it could be worked it had to be crushed and separated from dirt and rock. In the early 1830's, Penfield and Taft developed a magnetic ore separator powered by an electromagnet designed by Joseph Henry. When the Crown Point Iron Company established new works in 1873 that required large-scale separating, a new separator building replaced the old double sawmill built at the middle dam in 1830. Ore cars dumped their loads at the top of the building, and a conveyor on the near side reloaded them with dressed ore. A heavy round iron pin anchored in the ledge served as the anchorage for a snatch block pulley through which a cable or rope operated the flume gate in the dam from the separator building. This point was the end of the railroad spur for trainloads of ore from Hammondville, where the cars dumped and the ore slid by gravity into a stone-walled bin to be roasted. It was then crushed and separated in the building that once stood on the foundations below. The first industrial use of electricity occurred here in the summer of 1831.