264 COALFIELDS AND COLLIERIES OF AUSTRALIA. 



opposite directions, the whole being covered with a layer of 

 compound-impregnated jute. 



The low tension cable is a single core, bitumen insulated, 

 and single armoured cable; suitable for a normal pressure of 

 600 volts. The core is covered with a separator of paper, and 

 over this is placed a cover of vulcanised bitumen. This is 

 served with two layers of bituniiiiised tapes laid on in oppo- 

 site directions. The armour consists of a single layer of gal- 

 vanised steel w r ires laid on in such a manner as to enclose the 

 cable in a continuous ring of steel. 



The trailing cables are 100yds. in length. The cable con- 

 sists of two cores, each insulated with a layer of pure rubber, 

 then two layers of vulcanised rubber covered with a layer 

 of rubber-coated tape, and the whole vulcanised together. The 

 two cores are laid together, and covered with a double layer 

 of rawhide woven protection, which is more flexible than wire 

 armour. Experiments are being carried out to make the raw- 

 hide distasteful to rats and mice. Where the trailing cables 

 are clipped on to the low tension cable, the wires of the armour 

 are cut and laid back over rings, which keep the wires in 

 place. The cable is grounded at intervals along its course; 

 but in case of a fault making the armour live, the cut armour is 

 connected with 7- 16th galvanised steel wire. 



The haulage is done by an endless rope (Fig. 170), driven 

 by one of Morrison and Bearby engines, with ISin. cylinders 

 and 3ft. stroke, geared down to 1 in 13. At present the rope 

 only goes in about 400 yds., but it will shortly be extended^ the 

 rest of the traction being done by horses. The skips are 

 clipped to the rope from 2 to 4 in a set ; and after being 

 weighed on a Pooley machine, are run into a side tippler above 

 a shaking? screen. The skips then run down hill till they are 

 picked up by a creeper chain, which carries them up to the 

 main track again. The creeper chain is kept taut by means 

 of a weighted pulley, which is suspended in a loop of it. The 

 slack that passes through the screen falls on to a mechanical 

 scraper, and is finally emptied into hopper waggons. The 

 large coal falls 011 to a steel picking belt, with wrought-iron 

 frame, so that boys can pick out pieces of band, the coal even- 

 tually being tipped into a shoot that guides it into waggons. 

 Provision has been made for erecting another picking belt 

 when it is required. The shaking screen, picking belt, 

 scrapers and creeper chain are actuated by an engine built by 

 Morrison and Bearby, having 12in. diameter cylinders and 

 18in. stroke. A throw-oft' switch is arranged on the outcoming 

 line between the tippler and the mouth of the tunnel. It con- 

 sists of a short length of rail, the lower end of winch is fixed to 

 the adjoining rail, while the other end is forced inwards by 

 means of a weight at the end of a bell crank. The weight, how- 



