MINING.

Otago Witness, Issue 2004, 21 July 1892, Page 19

MINING.

THE SEW HOY BIG BEACH GOLD MINING COMPANY. (Wakatipu Mail). Ihe area of river and beach ground held by the above company under lease is some 250 acres, and it comprises what is known by the Big Beach and Arthur's Point workings on theShotover river. The latter is where gold was first discovered on the river in 1802 by some shepherds of Mr W. G. Recs, runholder, and it quickly caused a diversion of the rush of miners which had just before collected at the Arrow river, where W. Fox an old New Zealand pioneer, had struck gold " heavily." The quantity of the precious metal which was obtained from the numerous beaches and beds of these two streams in those early days simply by means of the pick and long-handlesl shovel, tin dish, and cradle, is now a matter of history. At some places, such as Maori and Arthur's Points, by dipping into the stream, a few pounds of gold would be brought up with wash on the shovel — to use an expressive saying, it would often show as thick as peas amongst the black sand, some of the pieces being as large as that fruit. As a proof of the richness of the deposits on these streams and many of their tributaries, it may be mentioned that, in those palmy days it was a common event for 20.0000z or 30,0000z of gold to be taken away from Queenstown by export every week or two. But that era gradually passed away »as the more accessible deposits were obtained, for gold doea not grow in a day, and the accumulations of our gold deposits are probably the work of centuries — perhaps ages. Gold mining therefore became, more or less, a permanent industry, embracing the terraces ad well as beaches, &c. of the numerous streams throughout the Wakatipu district, which had been made to contribute to the wealth therein. And now the only way of working profitably— with few exceptions— is on an enlarged scale and w.ith improved mechanical appliances, such as is being done by the Londonderry Sluicing Company, Skippers creek and Upper Shotover ; Messrs Davis Brothers, Maori Point (also si uicers of terraces), and the Sew Hoy Big Beach Company. Similar remarks might be made with reference to another branchnamely, quart/, mining, the most successful companies being the Pho'iiix Extended and Gallant Tipperary Companies, Upper Shotover, and the Premier Consolidated and Sunrise Companies, Macctown, Anow River. However, the above remarks are made en passant, and a return will be made to the property and workings of the Sew Hoy Company, whose name appears at the head of this article. By far the greater portion of the Sew Hoy Company's claim or ground— aud hitherto the most profitable— is commonly known as the Big Beach; the whole of which, during the first years of the Shotover rush, was taken up by Europeans, many of whom made considerable "rises" from their claims. After the rich places had been thus worked, other parties holding some of the poorer portions became involved as to ways and means, and, getting into debt with one or other of the local merchants (who at that time gave large credit), one or two of the latter — more especially the late M. J. Malaghan, who was a moot enthusiastic supporter of mining— took the claims •over for moneys owing. After considerable trouble the latter arranged with a party of Chinese to work the ground on terms, advancing so much cash to them and the remainder to come from gold obtained out of the ground, thus guaranteeing them supplies as the work progressed. It was so n found, by the systematic way in which the Celestials set to work, that the poor ground would pay handsomely, and they speedily paid oft" some L2OOO and eventually left for the Kind of Promise — each with a competence. After the upper and easier portions had been thus worked by several large parties, Mr Sew Hoy, a merchant of Dunedin, conceived the bold idea of driving a tunnel through a high rocky spur at Arthur's Point to the lower end of the beach and thereby diverting the whole river through it so as to allow the whole lower portion to be worked dry— the tunnel to act as a tail race as well as shunting the water from its present bed through the gorge, and allowing this portion to be thoroughly tried. The idea, however, was not carried out, and it is therefore {in unsolved pioblem as to the value of gold contained in this mile of the company's ground. Certainly surveys were made by Mr L. O. Beal, C.E., and tenders called for the work, but the cost was found to be much above the estimate. Mr Sew Hoy, however, was still determined to try for some of the gold known to have been left in some of the deeper portions of the ground, and he next conceived the idi-a of working it by dredging, as is done in harbour improvements. He formed a small rompany of Dunedin business men (under tlie name of the Big Beach Company), who gave Messrs Kincaid, M 'Queen, and Co. a contract to supply them with a drudjj.capable of lifting 50 tons per hour from a depth of 14ft, to be worked by steam from a 20-horm.* X»ower inultitubular boiler to a compound surface condensing engine, which drove the necessary intermediate gearing aud belting, buckets, centrifugal pumps, and winches. Aftermany vexatious delays, stoppages, and alterations, the dredge proved by its operations that ground could be worked and made to pay whiah could not be got ! at by other means. Thus, being favoured by a tine winter, from ground previously valueless, (over SOOOoz of gold were speedily got, and this fact in ly be said to be tho diiect cause of the late dredging boom which set in about August 18S9. So satisfied were the Big Beach Company with the results, which greatly enhanced the market value of the property, and so strong was the confidence of the outside public in it, that th» company wa-i induced to_reorKani-,e 1111 ler tho present title, and issueu a prospectus for that purpose, making the nominal capital LISO.OOO. The proprietors, however— although hiving, undoubtedly, a valuable going concern— had overestinuited the credulity of the public, and the jiominal capital was after reduced to L 120.000 in fiO.OOO shares at L 2 each— at which figure the company was successfully floated, and 5(5,000 shares were allotted when the list finally closed. With the increased capital a contract was entered into with Messrs J. Anderson and (5b., of Christchurch, for the construction and equipment of the three new aud powerful steel dredges now at work, a short description of which may piove of interest to other mining companies :— The hulls are each 00ft long by 16ft wide, and 7ft deep, the plating being from one-fourth to live-sixteenths thick, secured to angle steel frames placed at 2ft centres, and stiffened at intersections with gusset plates, the floor joist being H sections, secured to deck beams by thirteen-four wrought iron tie pieces placed on intermediate frames. Each hull is further strengthened by being divided into four water tight bulkheads, one of which contains the engine, boiler, and centrifugal pump, aiuT another the winches and ladder-hoisting gear, that are driven by a horizontal shaft direct from the main engines. On the port side of each vessel a comfortable cabin is provided for such of the men as stay on board— it being floored and close lined with T and G stuff, and fitted with bunks and lockers. The engines are compound surface-con, dousing, working at a pressure of 801b of steam and an average vacuum of 23in. The centrifugal pump is driven at 500 revolution** per minute by Lancashire patent belting, worked from a largo pully on the main shaft to counter shafting fixed under the main tumbler framing, and it supplies from 1000 to 1500 gallons of water per minute for treating the wash dirt at a point 22ft above water line. The buckets (some 23, wiapable of holding about Scwt of wash each, and revolving round tumblers) are driven by a vertical shaft placed centrally between the two engine". A powerfully constructed friction gear wheel is placed on this shaft, and should any sudden or extra obstruction, such as logs or large stones, be jnet with the engines aud pump still go on, but the eour.se of the buckets is stopped until the .attendant removes either the obstruction or <lredge as the case may require. On the proper working of this ingenious and very valuable ■device depends in a large measure the satisfactory working of the dredge and avoidance of breakages, itfr Foord, the general manager, considers that, in addition to this contrivauce, a sensitive governor should have been supplied, so that a more regular speed could have been maintained than is the case at present — one of the principal objects to be aimed at in gold-saving

operations being to ensure a uniform water supply mechanically, which cannot be done now, and it has therefore to be regulated by the sluice man. The gold-saving appliances consist of a rather open screen placed just under the upper tumbler and over the sluice box, so as to arrest and separate the large stones from small gravel, the stones being at once shunted through a steel shoot some 10ft over the stern of the vessel, The finer stuff drops on perforated steel plates, and is further reduced till only fine sand containing the gold travels over the ripples and matting, and this operation is repeated some four times before the final discharge overboard. The whole of the appliances are taken up and carefully washed in warm water every morning, the residue, after still further reduction, being amalgamated with quicksilver, and retorted about once a week. The amalgam yields on an average from 58 to 61 per cent, in line gold, worth L 3 17s Cd per ounce. The plant is kept in first-class order from day to day, duplicate parts being kept to replace any worn ones or breakages which are carefully provided against by a daily personal inspection by the manager. Each dredge has a dredgeinaster and engineer who have proved themselves to be capable men, and give the work their sole attention, which often entaih many troublesome and disagreeable jobs, by both day and night— the Shotover being particularly subjected to sudden floods, even when no rain has fallen in the immediate locality. But it is surprising with what regularity operations have been carried on— the weekly average during the six months ending 30th ult., being something like 124 hours, exclusive of about one and a-half hour stoppages of each machine every day fer cleaning up, and some eight hours every five or six weeks for cleaning boilers and an overhaul of the engines, Ac. On each dredge nine men are employed (three at each shift of eight hours). Thirty-eight, men in all are in the company's employ every day, the average rate of pay being no less than 8s 7d per day. Nine horses are also required for carting coal and other material from Queenstown.

The average weekly working expenses of each dredge is something like L 55, made up as follows : — Wages, L 29 ; coal, LIS ; and maintenance, &c, LS. As showing the benefit derived by the district from this one undertaking, it may be mentioned that about L315U0 per half-year is paid away by the directors for wages and fuel alone. The amount of retorted gold obtained by the company from sth January to 30th June ■was 20(J!)oz valued at L 3 17s Cd per ounce, as the quantity of dross in the metal when smelted is extremely small. Much of the above information was supplied by the general manager, Mr E. Foord, to our representative, who was kindly shown over the workings last week by that gentleman. At that time No. 4 dredge— situated about the middle of Big Beach but slightly to the eastward— was working in a face about 200 ft wide, and the returns were found to be very satisfactory, notwithstanding the fact that the ground had been dredged twice before, but not to quite the same depth. No. 3 had opened out lower down, alongside the ground from which the old company obtained capital yields, and the present operations are thoroughly reproductive, with fair prospects, as it is maiden ground. No. 2 dredge, situated above the Aithur's Point bridge, had, till lately, been working the old Evening Star claim and. surrounding country. The success which has attended the operations of the company in this part of their property has hitherto been anything but satisfactory, owing very much to the heavy wash and depth at which the original beach, supposed to be rich, has been covered up by later drifts. The dredge, however, has set in at the old Morning Star ground, working at a depth of over 20ft, and it is to be hoped luck will turn

In the course of conversation with the manager (who is conversant with the subject and has had some experience in the matter) over the heavy outlay necessary to carry on operations, he assured our reporter that a sum equal to over LDSOO per year could be saved had electric power been used instead of steam, quoting the Sandhills dredge and Phoenix mine in support of his statement. If such is the case, and we see no reason to doubt the figures adduced, it would have made a wide difference in the working expenses had this power been adopted in the first place. The directors are all level-headed business men, and the chairman (Mr James Gow), who takes a very active part in the supervision of all financial doings of the company, doubtless hai well considered all the items that can be advanced in favour of the company's interest