The Cordova daily times., 1918-02-18
|NSRECTORSN HI. REVIEWS MINING
 OF TIE DISTRICT

ner s. Smith, in his annual report on the mining industry of the territory of Alaska, copy of which has just been received from the bureau of mines, de- partment of the interior, has the following to say of the Copper River district:
 Alaska Consolidated Copper Con- pany.-Development work was contin- ued at the company's property by the Eastern interests that hold an option. The mine is situated on Nugget creek, Ia tributary of the Kuskulana, and is about sixteen miles from Strelna, a station on the Copper River & North western railroad. During the winter power plant and compressor were installed.
 Great Northern Development Com pany.-only assessment work was done at the companys property, which is on Clear creek, tributary of the Kuskulana.
 "Hubbard-Elliott Copper Company Development was continued at the company's property on Elliott creek, a tributary of the Kotsina.
 "Kenneeott Copper Corporation
 "The corporation is working two mines, the Bonanza and the Jumbo, on Bonanza mountain, and is developing several prospects in the Copper River district. The mines are close together and about three miles from the con- centrator at the terminal of the Cop per River & Northwestern railroad. Both mines are connected with the coneentrator by Bleichert aerial tram ways, and at both most of the ore is chalcocite, with smaller amounts of ICovellite and copper carbOnates. The ore occurs in irregular bodies and seams throughout the limestone there is no regular method Of mining, but a separate plan is adopted for each ore body, according to it's size and slope In the larger masses tue high-gradO ore has been worked in benches; thC min ore has been blasted in from thu !. sides to fill the slopes and then drawI las needed. ThH limestone is hard anC stands well, permitting the opening 0 chambers Of a size that in softe 5 rock would be attended with consider able dangec,
 '''Fas 1ambo mine is opened by al inclined shaft, 30 degrees, with fevel 100 feet apart vertically. This shat is being sunk from the TOO to the S0( foot Eevel. Ventilation is natural, eJ lcept For the air from the machines an the sman blowers used to force ai g into the dead ends of the drifts. Tn tramway from the mine to the col centrator, completed last year, has scapacity of twenty tons an hour at & speed of 528 Feet per minute. It i l5;250 feet long and has nineteen tow grs, th1>se break overs, and three ter lsion stations. The track cable on tn 3loaded side is an inch and one-quarte lin diameter, On the empty side on inch, and the haulage cable is sever z I'eig'hths inch. Each bucket has a ca lpacfty of six cubic feet.
 The air compressor plant at tn Jumbo comprises two Ingersoll-Ran Imperial type, Glass XB-2, 15 and \ inches by IF inches, cross-compound two-stage compressors, each having = piston displacement of 513 cubic fee of free air minute, belted to 791 h. p. Westinghouse type c. w. motors enc lngersoll-Rand Imperial, Gas NE-1, l2 1-4 by I2-inch single-stag l compressor, with herringbone gea connection to a 50 h. D. Westinghous, . type c. S. induction motor; and twt small compressors, not in use at pres ent time, each with a piston displace ment of BIO cub feet a minute.
 "The Bonanza mine is opened by crosscut and inclined shaft sloping z, to B degrees, and a glory hole. A, the shaft is too small for good worl and larger part of it is in ore, new three-compartment shaft whicl ! will provide two hoisting compart ments and a manway, is being raised from the 600-foot level to the mair crosscut. This year a crosscut was completed on the third level to the Mother Lode side of the mountain, and raise driven to surface for air and manway. All ventilation is natural except for the air from machines and that from small blowers for the dead ends of advance workings.
 ''The Bonanza tramway, 15,450 feet long, with A towers, an angle station, and tension station, has a capacity of eighteen tons an hour at a speed of 452 feet minute. The diameter of