Patent no. 12915. Filing year 1881.

"Improvements on Submarine Gold Mining Apparatus," Ralph Borthwick, Moses C. Ireland, Edwin T. Jones, John Wilson and James Pierce.

This design for an underwater mining apparatus, patented in 1881 by five residents of Victoria, B.C., is one of several attempts by 19th-century entrepreneurs to cash in on the gold rush that transformed the newly created colony of British Columbia. However, as with the other gold rushes of the mid-19th century -- in California, Australia, South Africa and the Yukon -- timing was everything, and this mining apparatus, even if it worked, likely came too late to make much of an impact.

Gold was first discovered at the junction of the Thompson and Fraser rivers in 1856. The resulting frenzy of mining activity attracted thousands of prospectors from Canada, Europe and the United States. It even prompted the 1858 founding of British Columbia, Canada's response to fears that the United States might try to annex lands that until then had been controlled by the Hudson's Bay Company. The miners gradually moved further north along the Fraser and, by 1860, activity had shifted to the Cariboo region of B.C. This was primarily "placer" mining, in which gold was extracted from loose surface matter, from riverbanks or from the beds of rivers and streams. Equipment was minimal, and most miners sifted through silt with metal pans.

The rush peaked in 1863, when an estimated 10 tonnes of gold was removed from the Cariboo. At that point, the most accessible deposits were exhausted, and many miners moved on. Some larger companies formed, like the Cariboo Gold Quartz Mine Co. in Barkerville, which bought up smaller firms and continued to dredge the area creeks for years to come. It was the challenge of finding deposits in the beds of deep rivers that prompted the innovation of James Pierce and his colleagues.

Their apparatus consisted of a large, conical, watertight chamber that hung from a scaffold, which was mounted on a floating platform. Miners waited in a compartment in the top of the cone while it was submerged through a hole in the platform. Once the chamber reached bottom, water was pumped out of the compartment using compressed air, and the miners descended through a trapdoor to begin work, which consisted of shoveling sand from the riverbed through a sluice box designed to filter out the gold.

Underwater mining proved to be a popular source of inspiration. Other patents include Joseph Hébert's concept (12686)(1881), which only could have worked in creeks of very specific depth, and Matthews and Scurry's dredging machine (31445)(1888), which had a more flexible design. Pierce and his colleagues' machine is a rare attempt to build a submersible, but whether it could overcome the challenges of watertightness, air pressure and claustrophobia is another question.

It is unlikely that these designs had much industrial use, as the era of placer mining was nearing its end. By 1884, "lode" or hard rock mining had effectively taken over and moved much of the mining activity further south, into the Kootenay region. Lode mining, which required extracting ore from deep shafts and transporting it to smelters, required a higher level of capital and organization than most small companies could muster. Other metals, such as silver and copper, became just as important, and mining in B.C. gradually became a corporate affair.

References

Fetherling, Douglas. The Gold Crusades: A Social History of Gold Rushes, 1849-1929. Toronto: Macmillan of Canada, 1988.

"Gold Rushes." The Encyclopedia of British Columbia. Edited by Daniel Francis. Madeira Park, B.C.: Harbour Publishing, 2000, pp. 292-295.

"Mining." The Encyclopedia of British Columbia. Edited by Daniel Francis. Madeira Park, B.C.: Harbour Publishing, 2000, pp. 464-465.