Low Level Water Race - Victoria Battery
In order to treat this ore a gigantic plant is, of course, requisite [Waihi Battery – E], and, although that belonging to the company is the largest in the colony, it is now being increased by thirty head of stamps; and a fresh cyanide plant and additional kilns have also been constructed, and others are in course of construction. Three large kilns are in use, and two new ones are just finished, and the construction of another is in progress. These kilns are said to be capable of roasting 200 tons of ore at each charge.
The cyanide plant was, in January last, only in course of construction. It now consists of thirteen large circular vats and two sumps ; and eight additional vats are being added in order to meet the requirements of the extra crushing-plant now being erected. The first contract let was for twenty heads of stamps; the massive foundations, consisting of 4ft. of solid concrete, 6ft. wide, the bed-log being 28ft. long and 2ft. 6in. by 18in., and the upright logs, on which the stamper-boxes rest, are 4ft. 8in. by 2ft. 2in.
Since the completion of the above-mentioned contract ten additional heads of stamps have been erected, which makes a total of ninety head of stamps, weighing 9cwt. each, and the cyanide plant; consisting of twenty-one vats and two sumps. Although this extensive plant is erected, arrangements are now being made for the erection of another plant, either in conjunction with the present one or on a flat near the junction of the Waitekauri Creek and the Ohinemuri River, where it will be connected with the mine by a ground-tramway.
It is, however, really questionable, even after taking into consideration the large lode and the extensive quantity of payable auriferous ore in sight, whether it is a judicious undertaking to make so large an expenditure in the erection of additional plant, which would give a total of one hundred and ninety heads of stamps, capable of crushing, possibly, about 400 tons per day, or, say, 120,000 tons per annum. According to the market value, this mine now stands at about £l,000,000 sterling.
Notwithstanding the large success which has attended the Waihi Company, the Board of directors has determined to issue 10,000 new shares. Each of such new issue will be offered to the shareholders at a premium of £4 upon par value. Each of the present shareholders will, upon application, be allotted one new-issue share for every fifteen old shares now held, and on the payment of such new-issue shares as follows : 4s. per share capital and 16s. per share premium upon application, and £1 on allotment, making the sum of £2 paid. The balance, or sum of £3 to be paid in instalments of £1 each when called up, such new-issue shares not to be transferred or transferable until the whole amount due be paid. Upon allotment the new-issue shares will rank pari passu, in respect of dividends with old shares.
The explanation of the object for which these new shares are to be issued -is that it is being done in order to largely increase the number of stamps, and to enable the company to bring more water for battery purposes, and for other work consequent upon the extended development of the company's undertaking.
Water-races from Waitekauri and Ohinemuri Rivers, also from the Mangakara Creek, have been surveyed to the site at the foot of Thorpe's Hill, and during the year will be used for further crushing.
In view of additional increase to the water-power, it is proposed to construct a large race from Waihi to Owharoa. The whole of the water in the Ohinemuri River will be used, and also the water from the Waitekauri Stream. There are two ways in which this water-power may be used, either to lay a railway from the mine to Owharoa and erect another mill, or convey power by electricity from Owharoa to the present mill. This would give power to work more extensive machinery.
Inspecting Engineer to 31 March, 1896. P 70
The company have commenced to cut out the foundations for a mill of a hundred stamps near the junction of the Waitekauri Creek and the Ohinemuri River [the Victoria Battery –E]; they are also constructing a water-race from the Ohinemuri River, 8ft. wide in the bottom, 4ft. deep. and 13ft. wide at the top, on a grade of 1 in 2,000. This is estimated to convey sixty sluice-heads of water, and the fall from the end of the race to the place where a turbine-wheel will be placed to drive the stamps is about 54ft.; this will give about 270-horse power. It is, however, questionable if sixty heads of water can be relied on for many months of the year.
The following is Mr. Wilson's (the Inspector of Mines) report on the Ohinemuri district:—
The position for the new 100-stamp mill has been fixed near Owharoa, and extensive preparations have been made for its erection. This will necessitate the construction of upwards of twelve miles of water-races, the largest of which, starting from about a mile below the Waihi-Silverton Company's battery, and running to Owharoa—about six miles—will be 12ft. wide at the top and 4½ft. deep. The greater part of the work in connection with the water-races has been finished.
Work is also proceeding on about one-third of the total distance of the tramline, which will be about six miles in length, and on which a locomotive will be employed to run the quartz from the mine to the mill.
These works will entail the construction of three strong bridges on the line, besides a fourth crossing the river at the battery, on all of which considerable progress has been made. The driving-power for the mill will be obtained from the races by means of Pelton wheels and turbines.
Inspecting Engineer to 31 March, 1897
The company is erecting a new mill at Waikino, Owharoa, a description of which is given in the following extract from Mr. H, P. Barry's general report:—
Owing to some little trouble in getting the road-bridge across the Ohinemuri River completed, work on the new reduction plant was somewhat retarded ; but since the bridge has been finished and open for traffic the various works have been steadily pushed on. This bridge is a strong piece of work, 155 ft. in length, the main truss on trestles built on two concrete piers, the decking of the bridge being 30 ft. above normal level of water, which I think will insure its not being carried away by any flood which we are likely to experience. Wherever it was to the company's advantage, all the new works have been let by contract. In this connection seventy-four contracts have been let, nearly the whole of which have been completed. After getting quotations from several firms in different parts of the world, the contract for the supply of the one hundred head of stamps was let to A. and G. Price, of the Thames, New Zealand, who have already delivered a considerable portion of the machinery. The main shafting for the mill and the pulleys has been delivered, as also the two turbines and the two Gate's stone-crushers. The whole of the heavy timber for the mill is on the ground, including the twenty bed-logs, 4ft. 8in. by 2ft. 6in. by 18ft. in length, of good heart of kauri, which were sawn in our own kauri bush. The necessary excavations for these bed-logs, plates, and sills have been completed, and the masons have commenced the erection of the stone wall which is to carry the ore-bins. A considerable amount of work has been done on the tail-race, which has been taken out in a large open cut, but it is proposed to tunnel the rest of the distance. The following buildings were either completed or nearly finished at the close of the year : Store, 60ft. by 25ft.; sawmill, 80 ft. by 23 ft. ; carpenter's shop, 60ft. by 23ft. ; blacksmith's shop, 50 ft. by 25 ft.; machine and fitting shop, 60ft. by 25 ft.; office, 35 ft. by 29 ft.; locomotive-shed; store and dwelling house.
New water-races: The necessary motive-power will be obtained from a high-pressure system of races, having a fall of 198 ft., and a low-pressure system, having a fall of 54 ft. The high-pressure system consists of three races—the Mangakara Race and the Stony Creek Race, both tributaries of and falling to the Waitekauri Race. The Waitekauri Race, 6ft. by 2ft. 6 in. deep, and below the junction of its tributaries 7ft. by 2ft. 6 in., is upwards of four miles and three-quarters long, and commences at a dam a few hundred yards below the Waitekauri Gold-mining Company's mill. This race passes under the old kauri bush, through a tunnel 1,530ft. long, a portion of which has been securely cribbed where it passes through slidy ground. The Waitekauri dam is a substantial wooden structure, 16ft. high, with a spill of 68ft., the total length being about 170 ft., with the two wings built of heart of kauri throughout. I do not anticipate that we shall have any trouble with this dam for many years to come, as it was subjected to a very severe test soon after completion, when we experienced very severe floods, and it stood the test well. The dam on the Mangakara is a permanent piece of stonework, upwards of 30ft. in length, and running from 2ft. to 8ft. in height. The Mangakara Race, 5ft. by 18 in., is upwards of 22 chains long, passing through a tunnel 268 ft. in length. The dam on the Stony Creek will be a wooden structure upwards of 45 ft. in length. The Stony Creek Race is nearly half a mile long, 3 ft. wide by 18 in. deep. The pipe-line for conveying the water from these races to the mill is of wrought-iron, 2ft. 4 in. in diameter, and upwards of 1,200ft. long.
The low-pressure system consists of the Ohinemuri Water-race, four miles and an eighth long, 12 ft. by 4 ft. deep, running for the most part on the south bank of the river, but will cross at one place to the north bank by a high trestle flume, and recross again to the south bank after a distance of about a quarter of a mile. These crossings, although expensive, were unavoidable, owing to the nature of the ground. With the exception of these flumes just referred to and a wrought-iron syphon-pipe 5 ft. in diameter and about 475 ft. long, the whole of the race has been carried through a ground-channel, so as to obviate the constant repairs that would inevitably be necessary after the elapse of a few years where fluming to any extent on a water-race obtains. The dam on the Ohinemuri, at the intake of this race, will be a strong and solid structure of masonry. It was considered advisable to do this rather than to construct it of wood, so as to prevent any possible danger in the future through the wood rotting and serious damage being done to dams, bridges, flumes, &c, further down the river. The extra cost will not be very great. The water from this race, which has a fall of 1 ft. in 2,000 ft., will be conducted to two 200-horse-power vortex turbines by a pipe-line 4ft. 6 in. in diameter, branching off into two pipes of 3ft. 6 in. in diameter, fitted with equilibrium-valves for each turbine.
The length of the tramway from mine to Owharoa Mills is, approximately, five miles and three-quarters. It has been constructed of a gauge of 2 ft. 9 in., the smallest curve having a 6-chain radius. It has been well graded throughout, being, with only one exception (which has an up-grade of 1 ft. in 90 ft.), all down-hill with a load, the steepest grade being 1 ft. in 40ft. The line crosses from the north to the south bank of the Ohinemuri River, at a distance of two miles and three-quarters from the mine, by means of a strong truss bridge, upwards of 185ft. in length, and 30ft. 6 in. high from water-level to decking, and built of good sound heart of kauri and totara. The whole of the formation of this tramway has been completed, and upwards of three miles laid with heart of kauri sleepers and 40 lb. iron rails. All the culverts have been made with glazed earthenware pipes, which will be more durable than wooden culverts; and all the swamps which the line traverses have been drained by good substantial drains. The locomotive has been put together, and is now busily engaged ballasting the line and hauling building-stone to the mill. Twelve of the iron side-tipping trucks are on the ground, and we have received advice that fifty more, which should be sufficient for our requirements, are now on their way out from England.
Warden’s Report to 31 March, 1897
C 3A P6
The Waihi Gold-mining Company still maintains its great reputation, and last year saw more gold taken from it than in any other previous year. The mine itself has been most thoroughly and systematically opened up, and there is enough quartz in sight to last a very considerable time. The company has employed between five and six hundred men during the whole year, and the new works at Waikino have been carried out regardless of expense. The battery site required an enormous excavation, and the new battery, of one hundred head of stamps, will shortly be ready. A tramway, six miles long, for the purpose of bringing the ore to the mill, which is really a light railway, is nearly completed, and a steam crusher, for ballast for the line, is now hard at work. Two large water-races have been constructed, at a cost of £14,000, one from Waihi and the other from Waitekauri. To show the extent of the company's operations it may be mentioned that the new buildings erected by them at Waikino, consisting of dwellings, blacksmith's and fitting shops, offices, battery-house, tank-sheds, &c., completely cover 5 acres, and the money expended in these works, as may be gathered, is enormous.
Warden’s Report to 31 March 1898
The Waihi Gold-mining Company (Limited) have made great strides during the past year. Again it has put out a record return of gold for the year. Each year this great company increases its output, and it is expected for the year ending 1898-99 it will double the output of last year. Several important works have been finished, at a cost which must have run into six figures. The new 100-head battery at Waikino has been finished, and is now working as smoothly as could be wished. The two water-races to this battery alone cost £14,000. A new pump at the No. 2 shaft has been completed at great cost. This pump, I believe, is the biggest in New Zealand. It is capable of pumping 70,000 gallons an hour at a depth of 1,000ft. It is at present only down 370 ft., and working at the rate of six strokes a minute. It can do nine strokes. The railway, of six miles, has also been completed. The company are now busy putting in two more levels at a depth of 370ft. and 450 ft. respectively. Six hundred men are employed by the company, not including contractors, and the wages-sheet every month, excluding money paid to the contractors, totals up the very respectable sum of £5,500. The output per month, which is now close on £23,000, is expected to be increased to £25,000. The company have in contemplation the erection of another hundred head at Waikino as soon as the Union Waihi Company are in a position to take over the ninety-head battery at Waihi [they never did – E].
Inspector of Mines to 31 March 1898
Waihi Gold- and Silver-mining Company.-—
The operations of this company consist principally of driving and stoping in the Martha, Welcome, and Victoria lodes, which are supplying abundance of quart/, to keep the mill constantly crushing………. The new Victoria battery at Waikino commenced crushing on the 25th February with fifty heads of stamps, and, with the exception of trifling details, everything in connection with this portion of the plant worked very satisfactory.
Inspecting Engineer to 31 March 1898
………. The Victoria battery, at Waikino, recently commenced crushing, fifty stamps being employed. 37,164 tons of quartz has been treated, for a yield of 126,801 oz. of bullion; value, £143,533. There are five hundred men employed by the company, 310 being engaged in the mine and the others employed at the batteries and on surface-works.