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I have the honor to be, Sir,

Your most obedient servant,

FRANCIS HOWDEN,
District Surveyor.

J. T. Thomson, Esq., C.E.,
Chief Surveyor.

REPORT OF W. C. WRIGHT, DISTRICT SURVEYOR.

Wakatipu Survey District,
Queenstown, July 25, 1867.

Sir,—In compliance with instructions as per circular No. 41, I have the honor to furnish for your information the subjoined Report on the condition of that portion of the Wakatipu District immediately under my charge, and regret my not being able to enter more fully into detail in describing the various works, as I have not for several months been able to visit some portions of the field.

The workings at present being carried on are chiefly confined to the auriferous drift beds—the terraces of the Shotover and other valleys—in many of which distinct leads have been proved to exist at great depths beneath the surface. In quartz mining, with the exception of four or five instances, work is at a stand still; and in river or creek workings—that class of mining which at one time engaged the attention of almost the entire population—not more than a dozen companies are engaged.

It was anticipated, in the event of a favourable season occurring for the carrying on of river and creek workings, that many portions of the Shotover and other streams would again have a numerous population settled upon them; but although the Shotover has for months past been lower than has yet been known, comparatively few have been at work upon it. Some portions were, however, occupied, but an obstacle presented itself most difficult to be overcome. It was found that the debris from the many extensive sluicing operations had accumulated to a very considerable depth, and that expensive preliminary works in connection with powerful machinery, would be required for successfully working the drift beneath it. On the "Perfect Cure" Beach, below Maori Point, a company of miners cleared a paddock a depth of ten feet, expecting to have struck the wash-dirt, but not succeeding, a rod was put down nine feet six inches further without then reaching the bottom. There must in this place have been ten to twelve feet of silt and debris accumulated above the original bed. This is an extreme case, but everywhere along the natural course of the Shotover the beaches have been raised considerably.

An overshot wheel is in use for draining ground at Arthur’s Point, measuring 35 feet in diameter and 2 feet 9 inches between shroudings, and is intended to work to 15 horse-power when fully-supplied with water. Two others are fixed at the Big Beach, the one above the other, 20 feet each diameter and two feet two between shroudings; to these wheels are attached California pumps, the first being 41 feet long, two feet wide and five inches deep, and the other two 40 feet long, one foot eight inches wide and five inches deep; the latter two wheels are worked from the same race of water, but they are now, however, standing idle.

There are two undershot wheels on the Shotover above Arthur’s Point, and these constitute the whole amount of machinery of any importance used in river and creek workings.

Some excellent ground has recently been opened at the Big Beach, which is paying about £15 per man per week; and two extended areas and some ordinary claims have been taken up. These are upon ground which three years since, and previous to the river being turned, was a low terrace, with from 12 to 18 feet of drift overlying the wash-dirt. The effect of diverting the stream has been the complete washing away of the superincumbent drift, and almost laying bare the wash-dirt over an area of several acres. The river itself is now running on wash-dirt which will probably be worked.

In quartz mining, I regret to state that, with a few exceptions, a general stagnation has taken place, which is doubtless attributable to the fact of the first crushings not having realised the anticipations of shareholders, and also to the many delays which occurred in getting machinery to work. The long-continued drought has also been a serious drawback, as the three machines that have been erected are depending entirely upon water-power. As a general thing not more than four or five of the stamps of each battery could, for want of sufficient water, be kept at work; for which reason, although the stone passed through has been exceedingly good, the quantity has been small.

I visited the principal reef claims a few weeks since, and found the following to be the condition of the works.

At the leasehold of the "Great Scandinavian Company" a tunnel had been entered into the reef perhaps 150 feet in length; in the face was a solid, well-defined reef, bearing nearly east and west, and being of about six feet in thickness. A stoop had been opened up into the same kind of stone to a considerable height. In addition to this, work was being carried on upon a flat vein of white quartz, lying in a rubbly, oxidised fuccau, some of which, with the quartz, was being removed to the machine. I procured from this place some of the best specimens I have seen in Otago. A drive 60 feet below this has pierced the reef. This Company’s machinery is erected at the junction of Murdock’s Creek with Skipper’s Creek, about twenty chains from the reef and 200 feet below the level of the adit. The quartz is taken by trucks to the mouth of the tunnel, and thence by tramway to a shoot overhead the machine, down which they are emptied, when they fall into a paddock capable of holding about 1,000 tons. A shoot from this fills other trucks, which are rolled away to the top of the machine house, where it is deposited in the hoppers of the machine.

This battery is self-feeding, for by a very simple contrivance one of the cam disks of each sets of stamps is made to drop on a hammer-head, attached by a lever to the hoppers, and when the stone is low in the boxes it falls with force sufficient to open a valve, which admits a certain amount of quartz to the stamp-beds. The stamps are 30 in number, and would require about 32 horse-power to be kept in motion.

The first wheel attached to this battery was a Scheile’s turbine, having a feed-pipe of 54 feet in height and two feet in diameter, the orifices being about 60 inches; but it was found not to work, as no more than two feet of a head of water could be obtained. The orifices were then partially closed, when the water rose to 40 feet, and five stamps were thus put in motion; eventually another wheel was procured from Dunedin—a Whitelaw’s turbine—which appears to act very well. Twenty stamps have been put in motion, and 15 worked up to full speed, but want of water has prevented the use of more than five, except at intervals when rain had swollen the creeks.

The yield per ton I am not able to give, as I have not had an opportunity of enquiring, but judging from the quantity of stone removed, and from the amount of gold sent down, it must have been satisfactory.

The Otago Company had, in the early part of the season, two or three excellent crushings, and were induced to place eight extra stamps to their battery, which now consists of sixteen; their wheel is a Whitelaw’s turbine, two feet six inches in diameter, having three arms; it is worked with a head of water of fifty-seven feet and a pipe eleven inches in diameter. The mine is fully a quarter of a mile away from the machinery, which stands in Murdock’s Creek, and a tramway, built altogether of timber, connects them along which the quartz is carried by trucks. The tunnel from which the quartz is at present being taken is on the west side of Murdock’s Creek, and the reef, when last I saw it, was about five feet wide. Two