Slowly, progress is made on the building of a crushing mill for extracting gold from the reef ore. Delays, the dam, design of the mill, opening ceremony.
Various misfortunes slowed down the construction of the mill:
Meanwhile the work of putting up the mill got on very slowly. The A.S.N. Co.,1 whose idea of handling machinery is to raise it to as great a height as possible, and then suddenly drop it, contrived to smash some of my heaviest castings in landing them on the wharf at Mackay. I had to send to Melbourne to get them replaced, and this caused a delay of several months.
1 The Australasian Steam Navigation Company, always known throughout the colonies as the A.S.N.
A dam was constructed to supply water for the mill:
Water was so scarce in the creek on which the diggings lay that I was obliged to put up the mill a mile and a half
From a February 1882 issue of the Mackay Mercury newspaper:
Besides spending a very great deal of money with his partner Mr. Rice, on the place, Mr. Finch Hatton who is generally resident here, has gained the respect and goodwill of every digger on the field to a man. |
Damming a Queensland mountain-creek is no joke. The violent storms which occur, and the heavy freshes that they cause in the creeks, make it necessary that any sort of dam should be remarkably solid.
The creek here was about 120 feet wide, and there was about ten feet of drift in the bottom. Of course it was necessary to cut a trench through this, right down to the bed rock, and fill it with clay, for the puddle-wall. The trench was three feet wide, and in it I sunk a double row of piles a foot thick, to support the frame of the dam above. Horizontal logs were laid against these and in between them, and this formed the centre wall of the dam. The amount of labour connected with this work was very great. ...
Had twenty-four hours more been given me to finish the work, I believe the dam would have been there to-day, and for twenty years to come. The by-wash was almost finished, and there were only a few feet more of the stone facing to be done. Those few feet, however, settled the fate of the dam. There came one of the most brilliant storms I ever saw. Queensland, at all times, can be relied upon to crowd more thunder and lightning into a minute than most countries can into an hour, and no better place for a display of the kind can be imagined than the valley of Mount Britten. It is a perfect funnel for collecting rain, about five miles across the centre, narrowing down to a few hundred yards at the mouth, where the dam across the creek was situated. ...
...When this particular storm broke over the valley I was up at the reefs, a mile and a half above the mill.
It was about ten o'clock at night, and deadly dark; but I started off down the track at once to see how the dam would stand. ...
The track crossed the creek twice between the reefs and the mill, and when I started up in the afternoon the creek was not running at all. At the first crossing on my way back it was only ankle-deep. The next crossing was half a mile lower down; and, though I ran all the way, by the time that I got there there was ten feet of water in the creek, running like a mill-race.
The lightning made the whole place as light as day now, and, as the crossing seemed to be clear, I soused in and got out all right at the other side. As soon as I got down to the dam, I saw at once that it was doomed. The by-wash was of no use at all to take the overflow. It had never been intended to do more than relieve the pressure, as the dam was an overshot one. But it was the few feet where the stone facing was still incomplete that ruined it. The water got a start there, and gradually ate away the whole concern like cheese; and in six hours there was nothing left but a few piles sticking up to mark where the puddle-wall had been.
Holliman was standing watching the destruction of the work, looking the image of despair. The rain was coming down in sheets, but nothing could get him away. He looked so utterly miserable, standing on the edge of a foaming creek, with the water running in streams down his back and out of his boots, lit up every now and then by a purple streak of lightning, that I went into shrieks of laughter at him. ...
This settled the Mount Britten dam. It cost over £350, and would never have been any use, as from some subsequent working we found that there was an old underground course of the creek in one of the banks, through which all the water would have escaped.
Finch-Hatton described the construction and operation of the mill in considerable detail:
In laying the foundations of my stamper-boxes I went right down to the bed rock, with a trench twenty feet long and four feet six inches wide. In the bottom of this I laid three feet of concrete cement for the foundation of the bed-logs. The bed-logs themselves were two splendid sticks of curly red-gum, nineteen feet long, sawn square twenty-four inches by twenty-one, and bolted together with two-inch iron bolts. These were laid horizontally in the trench. Three upright piles, five feet high and twenty-four inches square, standing on the bed-logs, formed the foundation of each stamper-box. These piles were very strongly bolted together, fitted with the utmost nicety, and levelled with the accuracy of a billiard table.
Each stamper-box was a solid casting, weighing nearly a ton, about four feet long, four feet high, and fifteen inches in width.
In each box five stampers work. The stampers are raised about ten inches, and then allowed to fall, by means of a shaft which revolves overhead, which is fitted with "cams" or "wipers," which give two drops of the stamper for every revolution of the shaft. The weight of each stamper with the shank, head, shoe, and disc complete, is about eight hundredweight. They work close together in the box, and underneath each is placed a die of hematite iron, and between the bottom of this and the floor of the box itself a layer of quartz is always placed, to prevent the shock of the stamper's fall from breaking the box.
Round the boxes is placed a frame of heavy cross-logs to support the columns upon which the cam-shaft works. These logs are kept quite clear of any contact with the foundation of the boxes, so that the inevitable jar of the constant fall of the stampers may not injure the rest of the machinery. The shaft is worked by belting connected with a stationary engine, which can be instantly disconnected on to a loose pulley-wheel.
At the back of the boxes are the quartz-shoots into which the quartz is tipped out of the drays from the reefs, and broken up into pieces about the size of a man's fist. The feeder stands here with a long-handled shovel, and slings the quartz into an opening at the back of the box.
There is a good deal of art in feeding the stampers properly, and a good man will run a ton a shift more through the boxes than a duffer, with the same number of revolutions to the minute. If he feeds too slow, of course there is a waste of power, and he is liable to break the dies by letting the stampers fall on to them too clean. On the other hand, if he feeds too fast he chokes them, and wastes any amount of time that way. A feeder takes a twelve hours' shift right on end, and a very monotonous occupation it is.
In the front of the box is an opening about two feet long and a foot high, fitted with gratings. The fineness of the gratings used varies according to the coarseness of the gold in the stone crushed, but from a hundred and eighty to two hundred and forty holes to the square inch are the ordinary ones. A constant stream of water is kept flowing through the boxes while the stampers are at work, and the stone is pounded up inside till it can only escape in the form of fine mud through the gratings.
From time to time a little quicksilver [mercury] is thrown into the boxes, and all the coarse gold collects in the form of amalgam.
Below the boxes are the tables upon which the fine gold that escapes from the boxes is collected. These tables are sheets of copper on wooden frames, and have a slope of about half an inch to the foot. There are three sets of them, and at the end of each is what is called a quicksilver ripple, which is a solid piece of wood with three troughs cut along it, about two inches deep, each a little lower than the other, and filled nearly full of quicksilver. The copper tables themselves are faced with quicksilver, which is kept constantly bright by the use of nitric acid or cyanide of potass.
Keeping the tables and quicksilver in good order is a science of itself, for, unless the quicksilver is lively, quantities of gold are lost.
The water flows from the boxes along the whole length of the tables, carrying with it the tailings from the boxes and the fine gold. This last is caught by the quicksilver, and hardens on to the plates in amalgam. From time to time this is scraped off as the crushing goes on, and the tables faced again with fresh quicksilver.
The man who attends to the tables, and to the retorting and smelting of the gold, is called the "amalgamator." Good men at this trade are scarce, and will easily earn from four to six pounds a week on a Queensland diggings. Even with the greatest care, and first-rate tables, a good deal of gold always contrives to get away. The tailings, as they are called, that have passed over the tables and run away into the waste drain, are analysed from time to time to test the waste of gold that is going on.
This process, above described, is the simplest form of crushing quartz, and is only fit for stone which contains gold in a pure form, unmixed with pyrites, galena, and other abominations that drive an amalgamator out of his mind. Where these exist, the tailings have to be separately treated, with more elaborate contrivances.
The tables lie close under the stamper-boxes, but great care is taken to keep them from actually coming into contact, for fear the jar of the stampers should interfere with them.
Having got everything ready for a start, we fixed on a day for christening the mill, and my brother's wife (1) came up from the station, forty miles away, to perform the ceremony. After some consideration I determined to call the mill the "Sabbath Calm." Anyone who has ever lived near a quartz mill will see at once that the name was not altogether inappropriate. The row made by the stampers is perfectly deafening. They go on, when quartz is available, from six o'clock on Monday morning till six o'clock on Saturday night, and no one who has not been maddened by the incessant din for a whole week can thoroughly appreciate the repose that Sunday's quiet brings with it.
The christening morning broke fair over the valley of Mount Britten, and, if the sun thought anything about it at all, he must have been startled at the change which a few months had made in the wilderness. The mill itself was a most imposing sight, with its vast expanse of galvanised iron roof and tall brick stack; and anyone who scattered a glance over the tremendously heavy machinery, fitted with all the most recent improvements, and faultlessly erected, would have found it difficult to realise that he was in the heart of the lonely mountains of Queensland, where, eighteen months before, the kangaroos and wallabies had had it all to themselves.
All the men who were working for me had a holiday in honour of the occasion, and all who were not gave themselves one, so that the whole population of the diggings assembled to see the start. They had all treated themselves to a wash in the creek, and everyone who could had fossicked out a clean shirt and a flash-coloured silk handkerchief as a tribute of respect to the important day.
The old doctor was in splendid form. He had been saving himself up for the occasion for ever so long, and, I believe, had drunk nothing for a week on purpose to enjoy himself all the more. In his excitement he had forgotten the wash in the creek, but he had climbed into an old pith helmet and a faded blue coat, which made him look far more disreputable than he did in his working clothes. He drank enough for four without ever turning a hair, and never stopped talking and laughing from sunrise to sundown.
Holliman surveyed his own completed work with perfect satisfaction, and without a particle of anxiety as to the working of the machinery in the aproaching trial. He had the confidence of a real artist in his own performance, and, knowning that it had all been done in the best possible way, he had not a doubt about the result. The amalgamating table was turned into a bar, and one of the men told off as barman, with orders to give everyone anything they wanted as long as the liquor held out. He had a couple of buckets full of rum, with a pannikin to ladle it out, and an enormous army of bottles of beer, porter, brandy, and whisky.
A bottle of brandy decorated with streamers of red, white, and blue ribbon was hung from the roof, opposite the fly-wheel. Punctually, at 12 o'clock, my brother's wife advanced, amid a solemn silence, and grasped the bottle. Holliman looked at me as much as to say, "I've done my part of the business, now you can start yours."
The steam was on, so I jammed down the lever. Slowly and smoothly the vast fly-wheel began to revolve; the bottle, discharged with unerring precision, was dashed to pieces against it; and the "Sabbath Calm" was fairly started, amid wild cheers from the assembled crowd. The old doctor nearly went mad with delight. He flung his old helmet into the air, and, waving his third pannikin of rum round his head, was about to give vent to the discordant bellow by which a German endeavours to imitate a British cheer, when he overbalanced himself and fell backwards into an enormous tailing-tub full of water. Far from discouraging him, this catastrophe seemed to delight him immensely. He was extricated, perfectly good-humoured and cheerful, and, having called for another pannikin of rum, he insisted on making a speech, to which no one listened, all hands being busily engaged in drinking success to the new mill.
(1) In January 1882, Henry Finch-Hatton had married Anne Jane Codrington, daughter of former Admiral of the Fleet Sir Henry John Codrington K.C.B.
