OUR GOLD FIELDS.

Otago Daily Times, Issue 827, 16 August 1864, Page 5

OUR GOLD FIELDS.

No. 7. THE MOLYNEUX. (B- OUR SPECIA- REPORTER.) Perhaps no-other workings in Otago have produced so much excitement among the mining community as those on the banks of the Molyneux River. The existence of gold in its gravelly beaches had long been known to the settlers in its vicinity, and I believe an attempt, prior to the discovery of sold at Gabriels and fuapeka, was made to test the value of these auriferous deposits; but through the inexperience of those who made the search, it proved unsuccessful, it was left to those enterprising prospectors Messrs Hartley and Reilly to prove that the bed and banks of this celebrated river were a remunerative field of labor, which they successfully demonstrated in July, 1862. i-ixe particulars of the discovery I have given in a former chapter.- It is now an established tact that the beaches along the whole course of the Molyneux or Olutha, from its rise at Lake Wanaka to its junction with the sea, are highly auriferous; but as it will not be necessary to particularize all the various workings tlu-ou.houfc its entire lenstb, I will just give an ncwuntot that part which is within the Dunstan District, aud which may be said to be the most interesting as well as the richest portion of its course viz, from •the Kawarau junction to the Fourteen Mile Beach, fourteen miles below the mouth of the Manuherikia River, and a total lengfa of twentysix m'les. *he Molyneux, through this portion ot its course, has an average width of from eighty to one hundred yards, by a depth in mid-channel ot about ten to twlve fathoms. The current is. a very rapid one, but not so much so as is generally supposed. 'In the ordinary state of the river when nofc flooded, and where there is an absence of rapids (for instance, between the Dun., stau and Manuherikia), it runs about four and a. half miles per hour; while in parts where it is narrow and rock-bound it will vary from six to eight. In its rises aud falls the river is very erratics and is subjected to sudden and violent floods, which would be exceedingly disastrous were it nofc for the Lakes at its head, which tend considerably to regulate the volume of water which, otherwise, would come down with enormous iorceafter heavy falls of rain. But for those natural reservoirs the prelude to a flood would be an immense "bore," or wave rushing suddenly down the course of the river, sweeping everything before it in its resistless fury, and inundating tne low lying country for miles around. As; it.is, it ha 3 been known to rise at the rate of two leet MANSE STREET.

per hour, as was the case in the great flood in July, 1863, when the river rose fully thirty feefc in fifteen hours, 'the same agency which regulates its rise does so with its fall. Considering that such a very many interests are hound up ia the rises and falls of the river, I have often wondered that the Government di 1 not hive an indicator placed in some well fiequented spot, taking a high water mark calculated from the height of known floods. .By this means parties at a distance might be ' supplied with correct information respecting ihe real state of the ny.r, whereby they would be able to calculate precisely how their respective claims stood m regard to their bein" workable. The season wnen (be river is lowest is at the latter esd of the summer; ater that ihere is generally a use, then the river falls.asain, am keeps down till tbe e«d ot August- or middle ot .*ep ember. A rise may be ■foretold, sometimes, two days before it takes pace, as the water gradually loses its beautifu -sea green color and becomes very turbid and muddy. . , * t The next question is, can tbs volume of water in tbe rive be reduced by artificial means, or portions of itscour.=e deviated fv-'in tbeir natural channel? Fr-'m careful observation, I have vo doubt that hofch may be 'one; but die uvsfc practical plan, I should iuiagu.e, is to divert at least one hai." ot the water flowing n by wav of the Kawarau River, which would reduce by a fourth that in the Motyneux. whi'h would 'be fct'fficifnt for all ordinary mining purposes, and I should • think that with pr.per management the woik might be made to pay for - itself. For instance, the course of the Ka waiau .from Lake Wakatipu to its junction with the- ' Molyneux is twenty five-miles, tbe who-e ol •which is highly auiiferous, and from theie fco " Portuguese Joe'V at Miller's Flat, ou the ' Ttfolyceux, is fifty more. Calculating both banks, it would give in one continuous line a length ot ISO miles, equal to 26,400 claims; wbich mis lit he taxed to the extent of three pounds each, a sum which the miners would gladly pay it the river could be permanently lowered, upon payment of fche fine or tax each miner should be allowed to register his cUim, with ihe privilege of transferring his light to another party, upon payment of a small fee By these means a sum of L 79 200 might be raised. Now, allow a third • less for non-payable ground, ifc would leave 152,800, which would be more tban snfficient for the making of an opening in Lake Wakatipu, a 'little below -Frankton, and tbe cutting of a ' channel into the Mataura by* wayof the' Dome Pass; the ancient, bed of that river at ihe time ■when the waters'of. the Lake formed one of its sources cf supply.' The.Jengfch of tiie cultmg would be about twenty-four miles, and could be executed for some few'thousand pounds less tban the sum 1 would propose to raise. With respect to turning the Molyneux at the Dunstan township, and taking itacioss the flat into the Manuherikia River a little above the township of Alexandra, ldo not think the undertaking would pay, as between the too places the quantity of gold is but limited. There are no great engineering difficulties in cutting a channel across the flat, but from the loose natu'e of the ground ifc would be very expensive; but e^ensupposina that this was acco/cplishedjtodivert the river it would be first necessary toconsfc. uct a dam, aud there is no place favorable for such a work, both '.tanks being; compised entirely of gravel and shingle, whicli troula melt away upon the first presence of water like " snow before the sunshine " To attach the dam, even if made, lo the banks, would be in .the ordiuary sense ot the ■word, an impossibility. From the same place, could there be a dam." the river might be turneu along the "foot of the Carrick Ranges, down as far as the Teviot, and perhaps fu ther. by which means some thirty miles df the richest part of , its course would be almost dried. But this would i necessitate some vety heavy cufctiogs, 'dtbou.b not greater than Ihe engineering skill of the present day could master, yet 1 much quesiiou , if there would be sufficient gold found to cover the expenses, rich as ihe river may be in auriferous wealth. The next plan of lowering the river, and one that bas been long in contemplation by the miners at Kawarau, is to clear the outlet of that river fiom the Lake at the falls at a time when the water was <ow, which might be done afc an expense of a ftw huo- j dred pounds This, if performed at a favorab'e ! season.might prove of considerable temnorarybene fit, eveu if it i.id not allow of many beach claims being thoroughly worked oufc, as from the ereafc' superficial area of the Lake it would take some five or six weeks before it would rise say twelve or fifteen feet. . . Before describing in detail the various local 1 lie* famous for the large yields of the precious metal. I .will eive some of the peculiarities under which it is found. In variably theie exists most gold in l*tt»e bights and bays wr.ere the water is still, and where the full force of tbe current is waro'ed eff by a projecting headbnd: also iv those places where there is ao indentation in the hi.<;h hd's bo deling on the river, as if large quantities of earth had either slioped or been wdsbed down by a stream of water, and tbe gold deposited by the earth bting dissolved upon coming iv contact with tbe current of :he liver. The gold is invariable- found in a layer ot coa'se . but tightly compacted gravel, having intermixed wifch ifc a number of very much water-worn pebbles of black ironstone, as well as a considerable quantity of black sand, formed by tbe wearing a-.vay of the river stones. It was at one time sunposed that tbis black sand and tin ore were identical, but ifc was soon discovered to consiifc of nearly pure iron. This layer of gravel is distinct by itself; ifc varies in thickness from.six inches to as many feeu and has an upper course of well water- won boulders as clcelv laid togelher as would bft the ca<=e in paving a stable yard; the only difference being that the boulders rest rather on their edges a^d point obliquely, in a direction between the centre of tbe river and the course of tbe current. In places where there are no " terrac-s" iuterveninar between the bills and the edge of the river, this layer of gravel rests on the bed rock, a sc't mica schist or reddish looking pipeclay, probably formed by the decomposition of the reck and colored by , sulphuret of u-on. Where alevel smooth rock prevails, bufc very little gold is fount*, the best finds bring on a soft larairated rocky boUom. When the *' terraces" run down fco the water's ed'ie, as is the case between the L'unslan and Manuherika townsliips, and which pi ol ably at one time was the site of an expensive lake, which doubtless was of fei-eat depth, as no primary foi mation can be found, the auriferous diiffc rests upon a bed of shing'e, or a recenty formed sandstone, and runs in patches oi from one to two hundred feet iv breadth, , preserving a course very nearly due north and south. Sometimes ifc will- be uppermost in the beach orbed ot the river, while at others it may be some five or six feet beneath it, evidently showing that the auriferous deposits are not tbe original ones, but of recent origin. 'I his peculiarity of the washdirt at the first of the rush to the Dunstan caused considerable uouble to the miners, who could not readily discover the whereabouts of the gold, and report says that Hartley -' andßeilly were near beine: lynched by the enraged diggers, wbo deemed themselves lo bave been hoaxed, but fortunately a short time soon discovered the exact strata in which the precious mefcal lay concealed. In a few places, where it is much exposed to tl-.e action ofthe current, the gold k in the crevices of tbe rock, and can be taken out intermixed with but very little dirt. In parts the cold is coarse in the river and fine in the banks, and in others vice versa. Some of the beaches have all fine gold, oihers all'coarse:' At the Half Mile Beach, just bslow "the Manuherikia Junction, I have seen piecss extracted weighing a quarter of an ounce. As a rule I should say tbat the gold has not travelled a great distance from its matrix ground, sluicing having practically demonstrated that whatever force of water maybe brought to bear upon the soil, the gold is always deposited but a short distance; from where the earth is first dissolved. Theriverhas, doubtless, acted as a huge sluice box, notwithstanding; which, there are distinct runs of gold not shaping a course in a line with its present channel, but rather across it ob.iquely. In parts, the beaches are a series of plateaux, descending like steps towards the centre of the river: such places are generally very rich—the gold occupying about the centre of tbe slip, or plateau, and I think this in a gr--at measure accounts for the opinion lately gaining ground that the centre of the river does not contain near so much gold as the banks. At the Twelve Mile beach, claims that were said to have been worked out at the time of the fall in . April . last, when the river fell to a lower level this last month, - other plateaus were found, and which yielded

equally as well as those previously worked. There is one thin, certain, and which bas lately been very clearly demonstrated, tbat the furtner you get towards the middle of the river the depth 0/ the beds of gravel ranidly decrease; and there is little doubt bu.: that in its extreme centi'e theie exists little bufc the bare rock. The large dredv ma- machine at the Manuherikia has almost, proved tbat mucb. consequently the gold would be in crevices, and not easily detected unless the water otuld be thoroughly drained off Afc the sume lime I do not believe Ihe centre of the river contains (he amount of gold wi'h which it is crediied. excepting iv those places where ifc is crsse'i by a lead, and where prospects of a J'jivorable place for holdiog it'exists. It d übfcless abounds in large quantities, for in such places toe further you-get into the river the heavier are the deposits. As yet our knowle ijr-e of the real wealth of this modern Pactolus is vevy incomnlete: time alone will enlighten uw on the subject. Tbat tbe banks aad beaches of the Molvneux will afford many years of profitable emnlovmeiit to out- mirrors there cm be no question, and doubtless mauy valuable discoveries will be made, especially now that attention is being so generally directed to those places which are removed from the near viciniiy of the water's edge.