MINING NEWS.

Alexandra Herald and Central Otago Gazette, Issue 411, 31 March 1904, Page 5

MINING NEWS.

lH The river has been falling steadily lefedurincthe weak,'tlie height last even- . Ing being about 6|f t above the ' nor- *"* ma!' mark at the bridge. The work of erecting the new elevator (Payne and Peck's patent) on the Alexandra Lead dredge has been completed, aud a satisfactory trial run was made on Tuesday. The dredge is now working steadily. The Perseverance No. 1 dredge is working 6teadily and keeps on excellent wash, her return of 62|oz for last week being a very satisfactory one. The No. 2 dredge is still undergoing repairs It is intended to place a silt wheel on the Molyneux Hydraulic dredge before die Iging operations are resumed. The dredge wi 1 thus be able to work to better advantage, and the difficulty that has lately been experienced owing to the accumulation of silt at the stern will be overcome. The Golden River dredge and claim were put up for public auction at Dunedin on Saturday last by Messrs Sievwright and Co., who acted under instructions from the solicitors for the mortgagees (Messrs Sparrow and Go.). There was a fair attendance at the sale, and bidding began at £l5O, and advanced to £325, but the property was passed in. It is understood that the reserve placed on the lot was £SBO, •nd there is every likelihood of the sew company which has been formed acquiring the property. The coal road leading from the Manuherikia Oo.'s road to the Sailor Bend c'aim will be completed this week. By means of the new road coaling operations at the latter company's claim will be much facilitated, and the expensive and unsatisfactory method of boating up and down the river will be entirely obviated. The road is being constructed by Mr J. £. Thompson, whose name is a guarantee that the work will be well done. A comparf called the Clutha River Gold Dredging Company, with a capital of £2500. has been formed to acquire the New "Vincent dredge, and put her on to work part of the Point d'O and the Royal Maori claims near Cromwell.

SILT ELEVATORS.

In view of the serious difficulties that many dredges experience owing to accumulation of silt at the stern, the introduction of silt elevators is a matter of interest to dredging companies. A m ichine of this description has lately betm fitted up on the New Gold n Beach Co.'s dredge, and, during a visit of inspection, we were pleased to note the thorough manner in which it did its work, practically the whole of the silt being carried up the main elevator and stacked with the tailings. The result now is that the stern of the dredge is kept clear of silt, and is in no danger of being blocked, as she was previously. The elevator was designed and erected by the company's engineer, Mr J. D. Kerr, who is to be complimented on the success of his efforts.

In passing, we may mention that the idea of an ausfliary elevator is as old a§ dredging itself, and, so far from being a complicated piece of mechanism, the silt elevator is the acme of simplicity. Bimilar elevators are employed on the immense lagoons connected with the Amur River, in Siberia, under control of the Russian Government; they were used by the late M« de Lesseps, both on the Suez and Panama canals, and are also much in evidence in some of the Californian workings.

The silt elevator on the Golden Beach dredge is of the simplest description, although Mr Kerr must have had more than one difficulty to overcome. His aim has e\idenlly been to combine lightness with strength, and at the same time utilise every facility for the success of the machine. The framework is composed entirely of Bin by Bin blue gum framing and kauri logs. The bed logs are ot blue~gu:r and are about 14ft long, overhanging the stern of the port pontoon by some 6ft. They are firmly secured to the deck, and would have been heavier but for the fact that they have to go between the main elevator driving shaft and the deck. Tht- uprights are 10ft high, and are surmounted by appropriate cap pieces. The whole frame work is stiffly braced by means of lin •teel bolts and diagonal timbers. Another obstruction is the derrick leg for the main elevator, which prevented both an increase in height and a wider framing. Another consideration for the designer was the boiler power at his disposal. This difficulty also has been satisfactorilyovercome. The first motion shaft making 120 revolutions per minute has a dividing pulley 12in in diameter fixed to it, and this drives a 48in pu ley secured at one end of the silt elevator driving shaft. To the other end of this driving shaft is attached a 12in bevel pinion which gearing into a larger bevel wheel fixed to the top tumbler shaft gives the silt buckets a speed of 12| per minute. The silt buckets have a capacity cf rather less that one cubic foot each, The top and bottom tumblers are each cast in onn piece, two rollers are secured to the diagonal bracing, the latter consists of two 7ft lengths of iron bark each Bin x 6in, and to these are secured substantial cast iron shoes at each end, the whole being made fast to yery strong blue gum backers attached to the uprights. The banging gear con<sistQpf two steel bolts, secured to specia'ly prepared castings on bottom tumbler shoes. The other end connects with a substantial iron bark yoke. The Whole weight of bottom, humbler <fec. is carried on a lin steel wire rope, affixed to a worm and pinion arrangement, which is firmly secured to the deck and is easily manipulated by one man. The

tables are oh the starboard pontoon, whilst the settling tank is hung to the bed logs on the port pontoon. A very simp'e conntrivance of chutes conveys the bile from the tank, whence it is elevated and discharged into the main trays and thence amongst the tailings, The weight of the whole plant is just on four tons.

DREDGING RETURNS.

The following are the returns for the week ending Saturday, March 26th, 1904 :

oz dwt grs Electric No. 2, Cromwell 104 0 0 Lady Roxburgh, Roxburgh 80 1 0 Golden Run. Millers Flat 74 15 0 Golden Bed, Miller's Flat, 6dys 62 17 0 Perseverance No. 1, Alexandra ... 62 6 0 Earnscleugh No 2, Alexandra 200h 60 0 0 Hessey's Waikaia 54 11 0 Otago No 2, Beaumont 43 0 0 Riae and Shine, Up'er Clutha ... 42 0 0 Dunstan Lead, Alexandra, 41 6 0 Sandy Point, Alexandra, 40 1 10 Sneddon's Freehold, Waikaka, wk 40 0 8 Eitrick. Roxburgh, 134hrs 29 0 0 Olrig.Manuherikia, 22hrs 25 3 12 Golden Treasure, Miller's Flat,... 25 0 0 Rising Sun. Upper Clutha 24 16 0 Central Charlton, near Gore, 137hr 23 2 0 Enfield, Waipon, 22 13 12 Waikaka Queen, Waikaka 21 14 0 Charlton Creek, near Gore 20 14 0 Royal Waimumu, near Gore 20 10 0 Upper Waipori, Waipori, 20 0 0 MacCharlton, near Gore, lllhrs 19 19 0 Waikaka United No 2, Waikaka 19 9 0 Matan, Clyde, 6 days... 19 0 0 Golden Gate. Millers Flat, 6dys 18 8 0 Tuapeka, Tuapeka Flat, 17 3 0 Enterprise No 2 , Alexandra ... 17 0 C Taniwha, Tuapeka River 17 0 0 Waimumu, near Gore, ... 16 16 0 Enterprise No 1, Alexandra 16 4 22 Lawrence, Tuapeka Flat, 6dys 15 17 0 Happy Valley. Tuapeka. wk 15 5 0 Nugent Wood, Waikaia ... 14 5 12 Waikaka Syndicate, Waikaka ... 14 0 0 hicago. Alexandra, 123hrs 13 10 0 New Prince Arthur, Sbotover ... 13 0 0 Cairntrodhe, Poolburn, 160hrs... 19 14 0 vVaikaka, Waikaka, I04hrs ... 12 13 <> Revival, Upper Clutha 12 8 0 Reliance, luapeka Flat „. 12 8 0 Sunshine, Upper (. lutha . ... 11 5 0 Otago. Miller's Flat, 5dys . 11 0 0 Central Mataura, Mataura, 10 4 0 Inchdale, near Palmeraton, .., , 10 4 0 Rise and Shine No 2 Cromwell 10 3 0 Mystery Flat, Waikaia,, 8 19 18 Junction Electric No 1, Cromwell 8 14 <■ Gabriel, Tuapeka Flat... 8 0 0 Cromwell No 2, Cromwell, ... 7 6 0 Inch Valley, near Palmerston ... 7 0 0 Cromwell No. I, Cromwell 6 5 0 Ngapara No 3, Nevis, 120hrs ... 5 18 O Total for 53 dredges 1339 4 22 Average per dredge 25 0 0