Water is Put to Work In Underground Mines
"Becoming California, a series that brings the California Gold Rush alive with the people who lived it."
by Don Baumgart
In the earliest days of underground mining everything not driven by muscle of man or mule was run by steam engines. Gold mining was no longer a business for loners; it now took a company with resources to sink the shafts and dig for the hidden yellow metal. At the North Star Mine in Grass Valley the steam was generated by wood-fired engines. Surrounding forests were being destroyed to provide firewood for the steam boilers. When Lester Pelton came down from nearby Camptonville in 1878, he brought a strange implement to George Allen, owner of the Miners' Foundry in Nevada City, and set up a demonstration. Pelton had brought a bicycle wheel with tin cups on it. He claimed to have invented a water wheel that would revolutionize the use of water for power. His secret was water-catching buckets split down the middle into two half-cups. After the demonstration, an impressed Allen agreed to manufacture the new design. First he built a single cast iron wheel and used it to run all the machines in the foundry. Mine owners who came in to buy parts for their stamp mills were shown the wheel at work. The mine owners saw Wheel One in operation and got the idea. They were running out of trees to burn and saw an approaching end to steam power in the mines. Soon after Wheel One went into operation, in 1895, an 18-foot water wheel was created to run machinery at the Massachusetts Hill Mine. At the time it was the biggest Pelton Wheel ever built. Water rushed through a cast iron pipe, then through a nozzle, turning the wheel, producing compressed air. The plant was the brainchild of Arthur De Wint Foote, a civil engineer sent to Grass Valley by the mine owners. The Pelton Company had guaranteed that the 10,000 pound wheel would operate at 75 percent efficiency, filling a six-inch compressed air supply line that powered the mine. Foote gave the completed installation a rating of 90 percent. The system worked so well that it won Foote the position of superintendent at the North Star Mine.
In 1898 its owners agreed to put in a 30-foot wheel to run equipment in at the North Star's central shaft. It was the biggest Pelton Wheel in the world, developing 1,000 horsepower at 65 revolutions a minute, its buckets travelling at 72 miles an hour. The 18-footer powered two air compressors; the 30-foot wheel drove four newly designed compressors, delivering ninety pounds of air pressure 2,000 feet to the North Star central shaft. In the mines the drills were air powered, and the air was used for ventilation. As the Grass Valley mines switched from wood-fired steam power to water wheels and compressed air, another power source was vying for attention: electricity. Before recommending Pelton Wheels and compressed air for the North Star Mine powerhouse A.D. Foote advised the owner that the insulation on the electrical equipment was insufficient for the wet conditions in Nevada County mines. Electricity was coming, but it was premature. It would be 35 years before the mine was electrified.
When declining gold prices in the 1950s brought an end to mining operations in the Grass Valley area, Pelton Wheels were propelled into obscurity by a 344 percent rise in the cost of water. The deserted powerhouse fell to other uses. Local kids would get into the building and push the big Pelton wheel around, riding it like a Ferris wheel. The big thrill was standing on the braces, holding tight, and going over the top. While their sport may have been dangerous, the kids didn't do nearly the damage to the old powerhouse that the salvage people did. Much of the historic iron went to the scrap piles before help arrived to preserve the remainder. The giant 30-foot wheel was saved by Phoebe Cartwright, a Grass Valley resident who raised $2,000 to buy the wheel back from the scrap heap. In 1961 the mining company deeded slightly more than an acre of land, containing the wheel and the old powerhouse, to the City of Grass Valley for the North Star Powerhouse Mining Museum, where you can still see "Wheel One," the first commercially manufactured Pelton Wheel, about the size of a car tire, an invention that changed gold mining forever.
Don is a former daily newspaper reporter, now a magazine journalist living in Nevada City, California. He has written articles for national publications taking readers to such diverse experiences as dining aboard California's Wine Train and a Nevada burger stop for outer space aliens.
- Temporary Super User
- 15 April 2012