THE SUTRO TUNNEL.

Otago Witness, Issue 1239, 28 August 1875, Page 16

THE SUTRO TUNNEL.

Among the most remarkable works of magnitude in mining being carried out in California one of the foremost is the Sutro tunnel, It is to extend a distance of three and three-fifths miles, and draw the Coinstock lodes to a depth of 2000 feet, and will cost, when completed, one million sterling. The companies on this great lode have agreed to pay a certain sum on every ton of ore raised from the mines on completion of the work. On the Ist November, 1874 the tunnel had been driven 7792 feet. During three weeks in October the tunnel waa driven 80 to 83 feet per week ; the last week in October 116 feet ; the size of the tunnel is 10 x 14, and in one month 360 feet had been driven by the Burleigh drill, being the heaviest work of the kind on record. Comparing this work with some of our Australian mining, we will take, by way of example, the adit driven into the Belmore mine, on the Great Western Company's property, near Icely. The size of their adit is 6 x 4|, and in eighteen months they have driven 480 feet. This gives 6 31 lineal, or 170 cubic feet per week, while the Sutro tunnel 116 x 10 x 14, gives 16,040 cubic feet, or nearly ten times the work in a given time. In the Hoosac tunnel the average progress under the old system was 49 feet p«r month. The work performed with the drills was at th« rate of 150 feet per month, at greatly reduced cost, effecting a Baying in time of over five years. Gre'ftt as ia the magnitude of the Sutro tunnel undertaking, there are several others eclipsing it ia extent and cost. In the Haxtz Mountains a tunnel was constructed fourteen miles long ; and in Saxony a tunnel of fifteen miles is in comse of construction, to drain the Frieberg mines. This has already taken several years, and will require forty years more to complete.

The Liverpool Daily Post would have us believe that the Prince of Wales has turned, if not exactly pious, at least very much more proper than he used to be. We are assured that his Royal Highness " has given up a life of fashion ;" that he is rarely seen in certain once oft-fre-quented card-rooms ; that he neglects the " Row ;" but, moat strange of all, that h« re studying ft© history of India (