Mohave County miner., 1909-01-16
Operating Three Big Dredees.

The Conrey Placer Mining company, ! which is engaged in placer mining by means of dredges in Alder gulch, at the town of Ruby, near the mouth of the gulch, has made extensive i'm provements in its plant during the past year.
 The company was originally organ ized as the German Bar Mining com pany and began operation. in Alder gulch in 1897, its plant being located ca what was known in the early days as German bar, just below the town of Adobetown, about two and one-half miles below Virginia City. The ground was worked by means of what was known as the Ledgerwood cableway. which consisted of a tower 30 feet square at the bottom and 90 feet high, tapering to a saddle block, about IS inches square, over which two-and- one-quarter inch wire cable extended some 100 feet to a stamp-propelled car which ran on a circular track. The digging bucket. with a capacity of a yard and a half of gravel, ran on this cable. It would dig a bucketful of gravel from the bottom of the pit and then was hauled to the hopper in the tower and the contents dumped auto matically into the Hume. The idea of this cableway was taken from those in use on the Chicago drainage canal, then in course of construction. This method was used three seasons, oper- ating during the summer months only.
 In 1899 the German Bar company was reorgauiz.d d into the COnrey Plac CT Mining company, so named for the COnre., ranch at the mouth of Alder gulch, which was purchased by the company from Philip Conrey for the sum of 30,O0OS. The company decided to discard the cableway and use the dredging method of mining, and, ac- cordingly, built what is known as dredge No. l, which was put in opera tion in the fall of 1899. This dredge was not built strong enough and was unable to dig the gravel without con tinual breakage, and after operating it a couple of seasons all the weak parts were replaced with stronger material and it was found to work admirably, and another boat, known as dredge No. }, was constructed and put in opera tion in July, 1902. This boat was built stronger than No. l and worked sue cessfully from the start. These dredges were of the open connected endless chain bucket type, there being buck ct every other link. The buckets on No. had capacity of six and one half cubic feet and on No. ? they held 10 cubic feet each. The gravel was brought up by the buckets from the bottom of the ponds in which the boats were floated, from a depth of from 30 to 37 feet below water level, and dumped into the hopper, from which it was washed by 1O-inch stream of water into a revolving grizzly with holes about four inches square. The larger gravel and boulders came out of the grizzly and fell onto an inclined rock chute placed crosswise of the boat, which guided the stones back into the pond and underneath the boat. The smaller gravel, sand and gold fell through the holes in the grizzly into sluice box which began under meath the grizzly and ran to the rear end of the boat, and discharged into a Hume. Rifles placed in the sluice box and Hume caught the gold, which was gathered by means of quicksilver.
 While these dredges were successful in saving the gold and moved large amount of gravel daily, they were op- erated by steam power, which was very expensive owing to the cost of coal, and the company decided to build an- other dredge, to be operated by cleo tricity. Accordingly dredge No. 3 was constructed and an electric power line was run to Ruby from the plant of the Madison River Power company, in the Madison canyon, some D miles distant. No. 3 was completed and placed in operation in September, 1906
 It is 13O feet long, IS feet wide, and the hull is eight feet deep. The dis tance from the surface of the water tc the tumbler shaft is B feet, which dis
 tance it elevates the gravel above the water. It digs gravel from a depth ot 43 feet below the surface of the water
 It is of the open-connected-endl