But the name that stuck was the product name of the Craig Company — the Monitor. The Monitors were powerful to say the least. When the water reached the Monitor it was compressed into a nozzle. The nozzle was from one inch to eight inches in diameter. The stream of water that could wash down whole hillsides was impressive to behold. In his multi-volume - classic History of California, the historian Hubert Howe Bancroft stated that an eight-inch Monitor could throw , cubic feet of water in an hour with a velocity of feet per second.
Other accounts of the force are less technical but just as startling. One description points out that a strong man could not swing a crowbar through a six-inch Monitor stream, yet another commented on the striking phenomenon of a fifty-pound boulder riding the crest of a jet with the power of a cannonball.
Documented evidence recalls that men were killed by the force of the water from feet away. The Monitors operated twenty-fours a day with the mines illuminated by high-intensity lighting or locomotive headlights.
The amount of water needed was enormous. At the North Bloomfield mine, sixty million gallons of water was used daily. Thomas Bell, the president of the company, estimated in that the hydraulic mine would consume 16 billion gallons of water in that year alone. The debris created was equally colossal. In , a group of government engineers estimated that hydraulic mining had deposited ,, cubic yards of debris along the basins of three rivers alone -- the Yuba, American, and Bear.
The environmental results were catastrophic. A typical description was penned in by Samuel Bowles, a visitor to the California gold country:.
Tornado, flood, earthquake and volcano combined could hardly make greater havoc, spread wider ruin and wreck, than are to be seen everywhere in the track of the larger gold-washing operations. None of the interior streams of California, though naturally pure as crystal, escape the change to a thick yellow mud from this cause, early in their progress from the hills.
The Sacramento River is worse than the Missouri. Many of the streams are turned out of their original channels, either directly for mining purposes, or in consequence of the great masses of soil and gravel that come down from the gold-washing above. Thousands of acres of fine land along their banks are ruined forever by the deposits of this character. The rocker is used for the same type of work as the gold pan in that it is mainly a prospecting tool. A man is able to wash 3 to 5 times more yardage than with the gold pan, and the use of the rocker eliminates much of the backbreaking strain of continuous panning.
On the other hand, the easy mobility of the pan as a prospecting device is lost. What people say Rather than using an active flow like a sluice, water was fed into the head of the rocker box manually using a tin can. Miners would usually nail it to the end of a stick so they could ladle water into the box.
As water was poured into the top, they would rock it back and forth like a cradle. This action would help to separate the lighter material from the heavier gold and black sands. A classifier screen at the top of the rocker would help separate out larger rocks. Gigantic floating dredges scooped up the river gravel while hydraulic cannons blasted hillsides and washed them into the streams and rivers.
The first hydraulic cannon was invented by Edward Mattison in Dredges and hydraulic cannons were controversial for their impact on the ecosystems. Legal battles between miners and farmers resulted in environmental controls.
Dan Boone has been writing since His work has appeared on CaribbeanChannel. He also holds a certificate in digital-sound engineering from the Trebas Institute in Montreal.
Regardless of how old we are, we never stop learning.
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