ALLUVIAL MINING ON THE WEST COAST.

Otago Witness, Issue 1725, 13 December 1884, Page 8

ALLUVIAL MINING ON THE WEST COAST.

'9 (By Our Special Rispobter^ The West Coast of the Middle Island is such an isolated spot that few residents in other parts of the Colony have any clear idea as to the nature and extent of the gold-eeeking operations now carried on thero. Most are inclined to regard Hokitika and its neighbourhood as a worked- out diggings ; and although they have heard abaut vast coal-bods in the Grey and Buller, and know, perhaps, more than they like to know about reefing speculations at Reefton, few have any knowledge of the really vast operations undertaken by several joint-stock companies in the neighbourhood of Hokitika, in order to carry on sluicemining on a large scale. I doubt whether it would be possible to find their equal in magnitude in Australia, and to do so it would be necessary to travel to California. In fact, it is from California that the idea was evidently borrowed to acquire extensive areas of kuown auriferous ground, and by the expenditure of large capital bring in an ample supply of water to sluice away the terraces into the river beds. Tho scene of the operations of one large Company on tho Coast is at Humphrey's Gully, about 10 miles from Hokitika. Two hundred acres of land form the Company's claim, their capital is £150,000, and for the last three yearr, in the face of great difficulties, they have persevered in their efforts to bring in a large water supply from a distance of six miles, part of it through a tunnel piercing a great hill for a distance of. 58 chains. As will be seen further on, this project is now close to its fulfilment, and the question will then be tested whether sluicing on a grand scale can be made to pay in New Zealand as it does in California. In the latter country many large sluicing companies have carried on Drofitable o ,erations with a yield of gold averaging 3d. per cubic yard. The thickness of their washdirt varies from 40f bto 260 ft. The thickness 6f the washdirt iv the Humphrey's Gully Company's ground is from 150 ft to 500 ft, and is described by independent experts to be of the most valuable character with regard to ease of working and probable yield. The top stuff, removed in fixing temporary tail-boxes, yielded an average of nearly 4d. per cubic yard for all the ground shifted, and it is stated that on either side of the present tail-race the yield obtained where, the reef was worked in shallow ground has run as high as lls per cubic yard — 110 yards on one side giving 14oz, and 200 yards on the other 20oz 53wt. At Ross, about 20 miles south of Hokitika, several companies are at work, some of them getting fair returns. The largest is the Rosa United, with a capital of £150,000. This Company hold a mining lease of 100 acres, and have bought out a large number of adjoining claims, so that they now hold the whole of Ross Flat. At one time the richest gold-workings on the West Coast were situated on this flat. Famous among them wag the Cassius claim, which in thirty-five weeks returned to its lucky sole owner, Mr Michael Cassius, 4772^0z of gold. Three companies on this flat, during 32£ weeks' working in an area of less than seven acres, obtained 11,543i0z. They were all flooded our, when yielding their best, through the failure of the drainage machinery, and the flat Has never since been worked. The Hosb United have now succeeded in solving the problem of draining the water out •of the flat and into the sea ; and having sunk a .shaft 392|ffc deep through eight gold-bearing layers, are noy/ driving to find some of the rich •runs already proved to exist in their ground. iShould these projects prove, successful they •will open up a great future for alluvial mining an New Zealand ; if they ,£,ail it goes without saying that very many people ivill lose heavily. The unforeseen delays in compieCJDg the preliminary works, and the severe •" calls" on shareholders., have caused Rome impatiance and anxiety, and no doubt the following account of the present state of affairs on tho ground will be of interest not only to BhareStiilders, but to all who take an interest in thn t (pcogress of mining industry. I may say that ; jl vls&ed the claims absolutely unfettered by • .any instructions or restrictions, and having juo mone/ interest in the success of tha .companies, my report can be taken as ithoroughly iey?artial. The Chairman of the ••two principal cora-panics (the Hon. J. A. Bonar; j*nd his co-directprs gave me every facility for making a thorough instigation. My opinion •of tee undertakings is that, they are thoroughly ibona Mfi ; the substantial natur.e of the works .and the heavy interest held by tije original ojiow that these companies do not ipartake of iha shady character of too many ■ v West Coast niini.Bg projects which have fleeced '■ #li** unwary. The .first company i will deal with is THE HUMPHREY'S GitfLLY UNITED GOLD-MINING COMPANY (LTD.) TJia ground held by this Company has {jeen known to be yayably auriferous for many : yeai-e, fcwjt, owing fci> the want of water supply, ■ was neve* properly tested. One private company of miaere attempted to bring in water i 'toy what is knov/a as the Caledou£a>? -race, but the difficulties of getting the water rGund the hill now being tunnoljed by the Company proved too great. ' Tha first attempt to worjt Humphrey's . Gully on an extensive scale was made in the ! latter part of 1881. Mr Brentnall, .C.E., was employed to report upon the available water su "^y > and nav J n fj explored the watershed of . 2£q U nt Tuhua for & distance of about seven ' jniles f rom the claim, ho reported that 13 creeks *co u^ a ' a PP e( i» giving a constant supply in dry wea t° 0? ot 12 to 14 Governmedtheads of watei'- The {&&&& for storage were •good, thero beint'' au oxeelioufc <sse for a lt>rge ■dam on Granite Creek, six ««les from Humphrey's. There v^re no engin^^tt^ difficulties in the way of raco-construotie ( n ; and the cost of m<iintetia».'' | 2a would be U^f small. Mr Brentnall also reported thit ihe> ■auriferous sluicing country w&iph .""uch a race •would command and supply v/aa the largest yet opened in Wetland As fliaiwing the value of this auriferous country, the w^fcings iin Greek's Gully— ono mile lowoi' dowja $je Arahura River than Humphrey's — were £6- j ferred to. This ground had been openad for >^G yeara; several partien were then jworlriug, i 'one of which (the Enterprise) commanded the whole supply — only amounting to three h^ads ffor half tho year. Tho face way about 40ft in 'height, and a largo area w.ia unworkable foi •want of wator. Coi-ree gold was obtained, •earaples up to 13dwt being procured, and also .•a nugget weighing 370z. In Humphrey*-., M'Donalds, land German Gullies a large ■extent of auriferous ground had beoa proved, •and in one claim tho depth of washdii-t was 300 ft In view of the dimensions eiaco attained by the Company's operations', it may Tao of interest to read the figures Riven as the probable cost of a race to carry 50 Government beads of water. The to£ai cost was to be £15,000-- £2400 being the co3t of tunnelling, and £2000 for dams. A company was formed in December 1881, •with a capital of £30,000 in shares of £1, to bring in a water-race sufficient to supply an area of five square miles of auriferous country

in the neighbourhood of Humphrey's, and to work an area of 100 acres which had been granted under a 21 years' lease to the Humphrey's Gully Water-race and Gold-Kiining Company (Limited). The proposal was to sell 40 heads of water to oth-?r parties, which would yield a revenue of £6240 par annum, and to work the Company's fjronud with the remaining 10 heads. It was estimated that the Company's claim would yield an annual return of gold to the value of £4800. The first permanent directors wero tbo Hon. J. A. Bonar (chairman), Messrs P. L D ; gn»->i, W. G. Johnston, M. L. W. Jack, J Pearson, J. Clarke, and G, A. Paterson (of Hwkitka), and Mr P. Oomiskey (of Auckland) ; Mr J. Gibson, managor. £ho same gentlemen still hold office, with the exception of Mr Peterson. During the first year £12,000 was called up, and the main works of tha Company taken in hand. Among these the mobt important was the " long tunnel," 58 chains in length, which has evor since proved a stumbling-block to tho Company. Two contracts were lot for driving the tunnel at each end in May 18S2, and the time fixed for its completion was April ISB3. In January 1883 it was too evident that the tunnel would not be driven in the specified time. In that month about 14^- chains of the inlet end contract was completed, and no serious obstacle was met with, but at the outlet end trouble had begun and very little progress was made. A contract had also been let for 3,f miles ditching, to be finished in Maich ISS'6. Plans and specifications had been prepnrod for a very largo work, known a3 tho " long flume," 50 chains 21 links in leDgth, and a contract let for the supply of timber for the flume, consisting of 212,000 ft of heart of rei pine, la ISB2 the Company purchased the extended claim and rights of O'Neill and party to M'Donald's Creek, together ' with a partly - constructed race and the claims of three other parties which were in the centre of the Company's lease. This caused an extra expenditure of over £9000, so it was becoming apparent that the affair was fast outgrowing the modest dimensions of the first project. The directors announced by circular on May 10, 1853, that for some time they had had under consideration the desirability of increasing their supply of water, in order to carry out operations on a mon extensive scale that at first contemplated, but as the undertaking was proving more costly thau had been anticipated, the present capital would bo insufficient for the completion of the original scheme. The proposals of the directors were: To acquire two large adjoining claima — viz , Clarke's leaso of 60 acres and the Miners' Amalgamated Sluicing Company's 29 acres ; to wind up the existing Company, and to form a new one, not under the Mining Companies Act, but as an ordinary joint-stock company registered under " The Companies Act 1882." Tho capital to bo £150,000, in 150,000 shares of £1, allotted as follows : 45,000 fully paid-up shares to the Humphrey's Gully Water-race and GoldMining Company ; 20,000 fully paid-up shares for Clarke's ieaso and waterrights, and 12,000 fully paid-up shares to the Miners' Amalgamated Sluicing Company. This left 73,000 shares to be allotted as contributing shares, and it was believed that the proceeds would be more than sufficient to moet the liabilities taken over, and to carry on the Company's extended waterworks to completion. These proposals were carried into effect ; tho necessary capital was readily subscribad (shares being now largely held in Dunedin, Auckland, and London), and the original Company was succeeded by the " Humphrey's Gully United Gold-mining Company (Limited) " From an interim report published by the directors of the new Company on 13fch November ISB3, I learn that at that dato the oni.let end of the long tunnel had been driven oight chains, where it had practically bsen brought to a standstill owing to a drift of quicksand, known locally as " pug." The directors wore obliged to take over the work from the contractors, and avoid the " pug," if possible, by means of a deviation from the straight line of the tunnel, in carrying out which they had obtained the advice of Mr W. N. Blaiv, M. Inst. C.E. The inlet ond of the tunnel had been driven 18 J chains, and woik was proceeding. Throe and three quarter miles of ditching was completed, the long flume v/as approaching completion, a contrast had been Jot for three quarters of a mile of open ditching which connected the race with tho dam site at Granite xCreek, tenders had baen called for frhe construction of the dam, and considerable progress mado towards openiDg up the ground whore it is proposed to carry on sluicing. Ten acres had been cleared of bush, and a temporary tail-race paved with iron blocks laid down a distance of four and a-half chains to the face of the terrace. One hundred and sixty-five ounces of gold was extracted from tho narrow strip of ground removed in bringing up the tail race, and this may -justly fte regarded as a proof of the richness of the ground held by the Company. On reaching the terrace, which shows a depth of 200 ft of " wash," a shaft was sunk, and bottomed at 30ft, to which level it was decided to lower the tail-race and permanent ; boxes. Tho firofc annual rppoit and balancesheet of the new CompPwny were issued on 22nd March 18S4. From the date of incorporation up to 11th" March 1884, £21,380 17a had baen called up; and the'expenditure during the same period is put down at £15,731 83 3d. The new engineer of the Company, Mr D. W. M'Arthur, C.E., reported on 22nd March I§S4 that the advice of Mr W. N. Blair had been acted on with success, that tho "pug" was finally mastered, and that the tunnel would be .completed in four or fiy.e months from that date. The distance then to b'a driven between both faces was ;21'3<9 chains. This estimate proved too sanguine. On the ljLth September last it was reported that " Ptfg" had again made jts unwelcome appbS- r JWW?e ; ?»nd that another deyiation was in progress f# £yoid the difficulty. At that date the !?ngtb of tonne} required to bo driven was B'BG chains'. " » nOiQ foregoing sketch of the Company's history aM ogeyafcion/3 will explain the position of affairs, accoiding to latest ifitforgn&tjon, up to the data of my visit. THE COMPANY'S CLAIM. f left Hokitika to visit tho Company's ■grn,viu<£ on the 27fch November last, and after driving .fivpr an excellent road through pine forest for 8. 4k£ ance °f about 10 miles, arrived on tho leasehold ,ia Humphrey's Gully. We put up the horscfl fti the hostelry rendered fnranus by iha great Archibald Forhea in his article on " Doughtoraa Scslp," Here wo are shown a splendid sample of coai'£&£old found in the neighbourhood by a private ijpfcrty of miners, and are assured that there £s plenty .of the name article to be got whun water is abundant. We listen to some forcible, if not polite, remarks concerning Mr Forbes' account of his visit, and find that the native!) are very Elvish astonished at his preference for fiction, as evidenced by his story of an imaginary visit to Doughtown, and lecture delivered to the admiring population thereof. The obliging Boniface provides himself with pick and tin dish and leads ,the ivay to the "face" in M'Donald's Gully. In a few minutes we find ourselves on the spot where the terrace has

been exposed for a height of 230 ft, showing an j immense body of washdirt consisting of fine gravel, There if a marked absence of large atones or boulders, which are found to be a gsoat hindrance in Rluicing operations on the Coast — notably at Kumara and R033, where they have often to be broken up with dynamite before they can be washed down tho tailraces. When this face has boen sluiced away by means of giant nozzles, it is estimated that the waßhdirton the face of the bill tit the back will measure the astonishing depth of 500 ft. To this faco a temporal tail-raco has boen cut, and, as already staged, IGSoz of gold was obtained from tho strip of ground removed in the operation. The boxes aye of a very largo size, being Bft 6in wide, by 2ft Gin deep, They are paved with iron bottoms, alternating with a chain cable and iron raiL Bffc long. From this point y.'o got a view of the area of.cured as a tailings site — a matter of very great importance to a company contemplating such extensive sluicing operations.. Thero ia a fall of lGGft from the end of the permanent boxes to the Arahura River, which is distant 30 chains ; and the Company has acquired a tailing site area down to the river of 80 acres. This ia exclusive of M'Donald and Humphrey's Gullies, which are proclaimed tailing sites. The total area of ground now held by the Company, which will be worked by tho rac3 when the tunnels are through, consists of a compact triangular block ot 200 acres, tha thickness of the washdirt varying from 150f b to 500 ft. Before leaving the tail-race site we washed a few dishfuls of sand and gravel, taken at random, and got vory good " prospects." Climbing to the top of the face wo came to a track running alongside O'Neill's race, and a short, brisk walk brings us to the mouth of THE LONG TUNNEL, at tho outlet end, where all the trouble has occurred. Here we find a cluster of huts occupiod by the men engaged in driving the tunnpl, and meet Mr M'Arthur, the engineer, who is uuder orders to remain on the spot until tho dreaded " pug "is conquered, The tunnel is Gib high and 4ft Gin wide. It is strongly timbered right through, props and cays being left every 3ft. The laths are perfectly dtoßßod, and closoly packed with moss. Tho first stoppage through meeting with wet pug occurred when about eight chains had been drivon at the outlet end. By means of deviations the difficulty was overcome, and good progress was made until a distance of a little over 14 chains was driven. Tho old enemy reappeared, and deviations on tho right and left hand side 3 were again driven, and firmer ground was. found in tho left side deviation, Oa the day I vistod tho tunnel the distance driven wan 1(? chains 25 links, acd they wßre thus 120 ft beyond the point at which the last stoppage occurred. The rate of progress is now about 42ft per week. At the inlet end of the tunnel the difficulties havo not been co serious, and it has been driven a total distance to date of 34 chains 89 links. At this point a wet grey reef has boon encountered, and as the tunnel at this end is of course driven down hill, there has been a considerable accumulation of water ; and pending the construction of a syphon, driving at the inlet end has been BUBpended for the last three months. A syphon oix inches in difimotsr and 23 chains long is being constructed, and Mr M'Arthur stated that ha expected it would be completed in a fortnight. When tho water is drained off, tho timbering of the tunnel at this end will bo completed and driving resumed. It will thus bo seen that on November 27 there was 6 chains SG, links to be drivpn in order to finish the loog tunnel. As sluicing operations cannot be started until this tunnel in through, and as all other works aro about ready, the probable date of the completion of the tunnel is tho all-important question for shareholdprs. Taking the present rate of progress at 42ft per week, as given by the engineer, tho work should be done in 10 weeks from tho date given above. At any moment, however, another stoppage might occur in the presont drive; but against this contingency has to bo placad the strong probability that driving will be resumed at the inlet end in a fortnight. Ten weeks, therefore, appears to be a reasonable estimate for the completion of this troublesome work. BRANCH BAOE AND TUNNEL. The construction of a branch race and tunnel has been begun, to carry a supply of water from the main race at the inlet end of Long Tunnel, through the hill to a convenient point for sluicing that part of the Company's property known as Clarke's lease. This means of conveying water might have been used to work all parts of the Company's property, and no doubt would have boen if Long Tunnel had proved a failure. But there is a considerable sacrifice of fall as compared with Long Tunnel. Tho total length of this branch race and tunnel is 2 miles 23 chains, and it is designed to bring 40 heads of water on to the southern portion of the property. The tunnel is 30 chains long. On the date of my visit it had been driven seven chains, and waß reported to be progressing steadily. THE HEAD BAOE, On the following day I made an early start on horseback to visit the works on the other _ side of the range pierced by Lp; g'Tu'nnel.' I ' proceeded along the banks' of ' the Kanieri River to a point whence it emerges from the Kanieri Lakej distant about 11 miles ' from f^okitika! I was fortunate ib respect of weather, an(^ had a charming yie'v? of the lake, i which, although small, will bear comparison, for beauty and grandeur, w^th many betterknown and vaunted ' New Zealand lakes. its shores are forjined by small rounded hills, .covered with ,th.c rich dense timber 'of tjbe T^est .Coast, and a noble background Js furnished by the rugged sides and snow-capped peaks of the alpine ranjje. With som.e reluctance my two companions turned away from this picturesque spot and led me into tlfe bush jn the direction of the prosaic ©oughtown. This trip through tho b»sh had been alluded to several times in ap ominous way, and I could not understand why the last two miles 'of the joiwney seemed to be looked forward to with somo d^rge of terror by my guides. J was soon eniigbisuM. Thp bush track was one of the vilest I have seen }n Ifaw Zealand, whiflh fa saying something. Aw 9> V.a]n effort to get our worsen through a swampy p3ge $?3 haffc the animals in charge of a roadman, and tramped through the swamp and scrub for about an hoar, sustained by a conviction that we rivalled the martyrs of old, so far as suffering waa concerned. We were not sorry when tha Milltown clearing came in viow. This brought us to a central point in the works which lie above the long tunnel. Erom th& inlet end of Long Tunnel there bxo two and a-half chains of fluming and a b&r%B open ditch cut, sft wide by sft deep, for a dietajpca of two miles, at a cost of £30 per chain. At wi|i point Doughtown is reached, and the water will i^are "be carried for five chains along a large fiuroe ,6ft wide by sft deep. The water is again carried in the same kind of open ditch as before described, pr.operly timbered where the ground is soft, until we Come to what is known as THE LONG FLUME. This work, which is about five miles above the claim, presents a very imposing appear-

ance, and is a striking evidence of the magnitude of the Company's enterprise. A first glance at the immense timbers which support the aqueduct high up in the air conveys the idea that you are looking at a bridge carrying a railway across ono of the broad rivers of Canterbury ; and it takes some time to realise the fact that this structure has been raised, not by a Government with borrowed millions in its purse, but by a few enterprising men determined to sluice away the golden terraios on the other side of the hill. This aqueduct waa necessary in order to carry the water over a deep, wide depression forming an extensive forasft swamp, and all the timber used in its construction was cut in the neighbourhood. The timber used is heart of rimu, cut in proper season, and has proved very suitable. Tho contract for the supply of timber for this work was for 212,000 ft, and tho total cost of the work £7000. Tho length of tho flume is 50 chains 21 liuks, tho height from the ground in some places 44 ft, and tho props average 12in square. The flume has a currying capacity of 150 heads of water. From the inlet end of the flume to the dam there is open ditching again, but of somewhat smaller dimensions, as there is here a greater fall. The average fall over the whole race is 8?t to a mile. From the inlet end of Long Tunnel up to the end of this piece of ditching — a distance of five miles — the race is complete, and ready for work at a moment's notice. In wet weather it haß been running full with water, and the ditching has borne the test well, the hard cemented gravel through which most of it is cut proving very firm. The race has occasionally been used for rafting timber required on the works lower down. THE DAM is situate on Granite Creek, six miles from the claim, and the real water supply is obtained from this point upwards, although a small supply is obtainable lower down from a few creeks. A favourable site has been obtained, covering an area of 11 acres 25 perches, and the dam is estimated to hold 5,500,000 cubic feet of water— equal to 55 Government heads of water for 24 hours, or 165 Government heads for eight hours. The embankment is now in course of construction at s, point where two terraces converge, the distance between them being about three chains. It is 180 ft broad at the base and Bft at the top, with stone pitching for the inner slope. The greatest height is 35ft, The slope on the inner side is 3to 1, and on the outer 2to 1. The puddle wall, for which excellont clay is found in tho neighbourhood, is 16ft wide at the base and 4ft at the top. The inner end of the off-take tunnel is very substantially built of Concrete, the cement for which had to be packed up to tho site. The dam will cost £6000, and Mr Prise, the contractor, says he will have it completed in the contract time, which is two months hence. Granito Creek, in the bed of which the dam is built, will supply, it is estimated, 20 Government heads of water. Mr Price's contract includes the construction of a race for 2\ miles above the dam— that is, to 8 miles 22J chains. This will intercept a number of creeks sufficient to supply water for sluicing two faces as soon as Long Tunnel is through. There are at present 80 men at work on Mr Price's contract. A further cxtonsion of this hoad-raco is contemplated, so as to bring in Mount Brown and Brentnall's Creeks. That would ba to a point three miles beyond tbe contract now in hand. This, it is estimated, would more than double the supply of water. Farther on the creeks aro numerous, and the Arahura River is only three miles distant from Brentnall's j Creek. Ai there are no engineering difficulties in the way of bringing water from the river at that point, there can be no question that the availablo water supply is unlimited. We had now completed our inspection of the upper works, and returned to Milltown. We retraced our steps painfully through the bn3h track, and rode leisurely back to Hokitika late in the evening, all feeling satisfied that we had done our work faithfully and spent a very pleasant although somewhat fatiguing day.