ANCIENT RIVER BEDS.

Otago Witness, Issue 1241, 11 September 1875, Page 15

ANCIENT RIVER BEDS.

Some of the sinking to work ancient river beds, in California, is a thousand feet deep. One of the largest of these river beds occurs in Sierra Nevada county, having a width of 100 to 300 yards, and a length of nearly 40 miles. The amount of gold taken from this bed has never been ascertained, but cannot be less than five millions sterling, and probably twice as much. The modern streams run at right angles with the ancient river bod. On the Tuolumne Table Mountain. the basalt was found to cover an ancient river bed to a depth of 300 to 1000 feet. After years of work the channel waa reached, and ten feet square of washdirt yielded £20,000 ; a pint of gravel not unfrequently containing a pound of gold. Ancient river beds are now being worked in Victoria, New South Wales and New Zealand. In New South Wales, there is one at Kandra and the vicinity, on the main Dividing Range, in which the wash is from three to 'thirty feet thick. The bed was originally a riverwash, but it has become in places partially cemented with oxide of iron. It consists partly of quartz, some of which is highly impregnated with copper. Single boulders of quartz have been met with producing nearly a hundred pounds worth of gold, The regt of the wash is made up of brecciated fragments of quartz, called by the miners "floating reef ;" also slate, diorite, albite felspar, hornblende augite, &o. The average yield has soarcely been ascertained as yet. This river bed has been traced about 30 miles, and again comes out in the Snowy Plains, in Victoria, where the Government intend to bore for and prove it. A body of four men owning what is known as the Scotchman's claim, at New Chum Hill, Kandra, have driven into the hill a distance of 1300 feet, and now find the wa3h has dipped away beneath them ; they have already been ten years at work here, occasionally tapping some part of the wash overhead. The total distance they have driven in all is about 2300 feet, illustrating an extraordinary case of perseverance under difficulties and privations in a most, severe climate, This fun of partially cemented wash appears" to have followed the main range, thus showing the great alteration of the surface since its deposition. It is considerably above the level of the sur* rounding country, and about 5000 feet above the sea level.