QUARTZ MINING IN OTAGO CENTRAL.

Otago Witness, Issue 2975, 22 March 1911, Page 79

QUARTZ MINING IN OTAGO CENTRAL.

(By Indian Chief and Billy Bttrlow.) There's gold in the mountains, There's silver in the mines. Dear Dot, —These words of the old song come vividlly to my mind as I take my pen tip to pilot you, and any comrades of oiur band who care to folow my tale, oyer the mine where I am at present earning my crust of bread and sundry other things which go towards keeping body and soul together in the bracing atmosphere of the wilds of Central Otago. Let us suppose we have borrowed the famous carpet and you aro all transported to a wild 1 , tuesocky, rocky, and scrubby country. For "State reasons" I shall not give the naane of the mine. You are landed on top of a steep hill, and if you look over the brow you see a creek far below you, and about halfway down several huts and tents perched among the rooks like 'flies on a windo.v pane. In theni the miners live. What catches the eye and holds it fast, however. is a suspension bridge swung right across the gully. I forgot to mention that you look into a gully from the top of that hili. The other side of the gully rises steeper and higher than the side you are on. On closer inspection you find the bridge is about three feet six inches wide, and swung like any other suspension bridge, and has guy ropes to the ground about halfway across to steady it. There is a 30in gauge tramline across it. and a tramway runs at right angles to it and leads to the battery. At the point where the rails from the bridge meet this line there is a turntable to turn trucks on and off the bridge. You must cross this bridge if you wish to see the mine, or else climb down the gully and up the other side, which is a big job. The bridge in very windly weather i-s nojoke, even for the staunchest, as, being light, it sways a good deal, and has that heaving motion of a ship at sea in a heavy swell. From the creek, to look up at it, it looks like a gossamer thrown from One rock to another. One*? across the bridg©, -we find a hopper for ore with a shute leading out over the line under which the trucks stand to load. Down the hill to' this hopper we see a curious tramline. It consists _ of three rails, the centre one accommodating both the upgoing and down-coming trucks;. halfway up it splits and forms a loop where the trucks pass. At the top is an apparatus which we call the hurdygurdy; it is a drum round which a rope is passed that is fastened at either end to a truck. The full truck going down pulls the empty one up. At the bottom there is a bar which knocks up the catoh and allows the door of the truck ta open, eo that the ore spills into the hopper. Just above the hopper is No. 1 drive. It is in some 300 ft, and, according to calculations, very close to tho reef. We go up to No. 3 drive at the top of the rise, where I was working for some weeks. This drive is in 200 odd feet, and there is a crosscut into the reef. We find two men at work on the face. One holds a drill (he is called a turner) and the other strikes it with a big hammer (he is called the hammerman). For every stroke of -the hammer the turner has to pull the drill back a little and give it a slight turn. A shot is fired, and one man gets the loose stone broken down with a pick while the other trucks ' it away out._ The scheelito can be seen in the quartz in this crosscut. Soheelite is hard to describe. It is very hard substance and very brittle. It is something like quartz, only duller in appearance, and is very heavy. It is used for hardening steel, and varies in value from £l2O to £2OO a ton. On arriving at the bridge again there is a loaded truck ready to cross. The man in charge pushes it off and stands on two buffers at the back, holding on to a ring at the back for the purpose. The trucks get some speed on. The bridge is 850 ft long, and a truck crosses in 25 second's, which is about a mile a iminute. The bridge is 267 ft above the creek; a fall from it woidd be a short cut to eternity all right. I was crossing it one night just after 12 o'clock (I had been on the 4 to 12 shift). and thought of the line, "I stood on the bridge at midnight." I wonder how the poet would have expressed himself had it been this bridge he was standing on. It is a weird sensation crossing it at mid- - night by the light of a Dietz lantern. On the home side again we find a rake of trucks ready to- start for the battery. Each rake consists of three trucks, and is pulled to a point half a .mile along the line by a horse. The line is two miles and a-half long. You all embark, and the driver starts the horse. At the point he unyokes his horse, ties it to the back truck, gets on the truck himself, eases the brake, and away you go. The lino is down hill the , rest of tho way. After a safe ride down you round a point, and there is Billy Burlow ready to take you over the battery. "There's no place like home," even if it 1 is an 8 x 10 tent in the tussocks. I afmf camped in an 8 x 10 tent, and doing great, things in the way of "baching." It is my first experience of camp life, and I like it immensely. My first camp was a triumph of a novice's art; and I am sending you a photo which will no doubt amuse some of my comrades if you can have it printed. Billy Burlow has' left the job since I started on this letter, and I have shifted' into' his camp, which is a good one, andi I make life endurable with books, magazines, and a mouth organ (not to forgot the Witness). ''' I'll try to draw a sketch of the battery

as I 6ee it at night, if you will permit me. Imagine Billy Burlow's scene lit up by half a dozen Dietz lanterns, -which accentuate the darkness around them. Billy Burlow and I are on shift together. I am Bitting on a. plank across the feed ehutes watching a stamper which is not working too well. Billy is crushinff coke for his engine. There is the stampity-stamp O* the stampers, belts are running, wheels are whizzing round, and the quartz is running into the stamps boxes. There 'i-s the swish of the water over the tables and. the sound of the gas engine. Above the rest the relentless din of the stamps gives one an idea of souls in torment. A glance out of the widow shows the stare twinkling serenely in the sky, and the comforting thought steals over one, "All's right with the world." I have a pet constellation. I do not know the name of it. I could see it from a window in the battery, and it somehow exercised a strange fascination over me. I wonder if you could tell me what it is? It is shaped something like a crown. There are three stars on the bottom and a bright one at the top. It is not quite overhead just now, but a little towards the north-west. When standing face to the north it is to the left of what is now the evening star. Well. Dot, I ami living in solitude just now. I am caretaker at the battery for Christmas week. All hands are away for a fortnight, and 1 I'm doomed to solitary confinement for a week. I came out on Christmas Eve, and this is now Friday night. The boss has been out every day but Monday and yesterday, so that most days I have had someone to pass a few words with. Yesterday one of the men came out to his camp, so that was a break in the silence. I can imagine what Crusoe felt on his isle. From Sunday afternoon to Tuesday morning about 11 o'clock the only company I had was sheep, rabbits, hawks, and a few hens. However, my exile ends to-morrow, and I'm looking forward to i trip to the city again. I echo the wortls Cowper puts into Alexander Selkirk's tmouth : O Solitude! where axe the charms That ©ages have seen in thy face? Hoping I have not bored you with my tale, I close with best wishes to all for a happy and prosper cms. New Year. —Yours truly, INDIAN CHIEF. Here the tale oc.ntinueth according to Billy Burlow. Dear Dot, —I promised I would write you a description, of this locality and also of the method of separating gold and scheelite from quartz. As Indian. Chief has explained about the visitor's magic carpet, etc., it now falls to my lot to show the visitors through the battery- Having met them at the tip head and having been introduced all round, I conduct them down the hill to whit is called the paddock. This is a large bin into which the rough quartz—or, as it n is Bometimes called, ore —is shot into from the trucks which bring it from the mine. Here it is held in readiness to be taken to the battery as it is required. As the party paused to take a casual glance at the rough contents of this paddock there suddenly arose a roar, and the ore in the middle of the paddock collapsed, much to the surprise of some of the visitors; but when they were taken down below tho paddock the cause of their surprise was easily _ explained. A man pushed his truck right underneath the paddock and pulled open a door, which allowed the one to drop out of the paddock into the truck. The truck was now pushed along a short tramline and the contents tipped into a shute. This shute leads into- the ore bin in the batter, and half-way down it is divided by a screen. The fine ore and small pebbles pass through this screen into the bin, and the large stones pass over the screen to a floor on top of the bin. They are then shovelled through a machine called the rock-breaker.

After watching the trucker for several minutes, the party was taken into the battery to see the rock-breaker at work. It was not going when we came to it, but your guide soon, remedied that matter by starting it goj,ng himself, and, laying hold of a, shovel that happened to be handy, he proceeded to show how the thing worked. This machine has a powerful iron jaw, which works back and forwards about 550 times a minute, and the stones are shovelled between- this- jaw and a heavy iron face. They are soon reduced to pebbles and drop into the ore bin ready for the stampers. The din of the stampers was rather deafening to those that were not used to it, and they wore glad to be outside again for a few minutes. However, I did not give them very long to recover, for I took them through another door into the stamper and engine-room. Here speaking, especially for strangers, was almost impossible, so the party bad to be content with looking at the machinery. We were only in here a few minutes when one of the the stamper G.hoes came off, and the battery had to be stopped while it was put on again. These shoes, which arc barrelshaped blocks of cast-iron, are wedged into the stamper heads and held there with wooden wedges. Sometimes the wedges are not thick enough, and the shoe comes off and has to be put on again. This job usually takes from 45 minutes to an hour to do.

While this was being done I explained the working of the suction gas engine, of which I am one of the drivers. The gas is caused by a mixture of air and steam being drawn through a very hot fire. When this gas reaches the cylinder of the engine it is mixed, witli a proper quantity of air, and when this mixtura takes place tho gas becomes very explosive. At the right moment an electric spark ia passed through it. and this explodes the mixture, the explosion giving the necessary impetus to the piston. The ore runs out of the bin into a machine called a feeder. There are two of these machines, one for each box of stampers; there are five stampers in each box. These machines are adjusted and controlled so that they just feed tho .right quantity of ore into the boxes. The stampers are worked _ by S-shaped arms called cams; there is a cam for each stamper, and the stamper drons twice to every revolution of the cam. The stampers weigh about nino hundred pounds each. and each stamper drops one hundred times a. minute, so you can imng-iiie the din that ten of them make. The ore. after it is crushed, is washed through a fine but strong screen, and the gold is caught by mercury, which is held on copper lates. The plates are first washed with a. solution of water and salammoniae, which causes the mercury to adhere to the plates. The scheelito is caught by a machine called the concentrator. As it was not so noisy here, the working of this machine was explained while it was in full

swing. It consists of a table, which can be inclined or made quite flat, and it is shaking- all the- time it is working. The scheolito is shaken over the end of tho table, and the sand is washed over the side and down tho tail-race into a paddock, where it will be* treated by the cyanide later on. By this process any gold that has escaped will be- recovered. This plant has not been installed yet. Well, this was all the visitors could see, and as it was late in the afternoon and Indian Chief and I had to go on shift, the visitors spread their carpet, and, wishing us good-bye, faded out of sight. Then Indian Chief and I got into our "blueys," or overalls, and, after boiling the billy and frying a chop, we- departed up to tho battery and commenced 1 our round of duties. Well, dear Dot, this is my last letter to your page, as I am already several months over the retiring age. I hope you will excuse the length of it, seeing that it is the last for many a day. I shall now close, wishing yourself and all D.L.F. the happieest of happy New Years. —Yours truly, BILLY BTJRLOW. (Robert, Crawford.) [lt was a very good idea that prompted you two to collaborate and send r* a description of your mine; the reading of it has been most interesting to me, and will I havo no doubt', be so to others also. I know nothing about the working of scheelite, though I have a couple of specimens of it in my possession. It is an ore that is certainly worth working at the price you mention. It is Germany that is tho market for all New Zealand scheehte, is it not? I am very- sorry to think that this is Billv Burlow's last letter to tho page, but he will perhaps be able to send us an occasional special article on some similar subject; and. of coxirse, there is ahvavs Old Wliters' Week. Good-bye, comrade'!—DOT.]