MACHINERY IN THE TRANSVAAL. 28t 



cheaply, as can be well imagined, but its duty was not very high. 

 None of these mills remained at work for a very extended period ; 

 indeed the result of their combined gross operations would pro- 

 bably be effected in one month with one of the smaller size mills 

 at present in use. At the end of 1886, a man named Rasch put 

 up a 5-stamp Sandycroft mill, driven by a 22 feet diameter iron 

 overshot water wheel, with buckets 3ft. 6in. wide, on the banks 

 of the Crocodile River, near Pretoria, to work some promising- 

 looking quartz veins in the range of hills to the north of Pretoria ; 

 but this plant, like most of the others, only ran for a limited 

 period. 



In these days the only fuel available on the Rand was bush 

 timber, and this cost considerably ; consequently it was the aim 

 to get a mill site near a river or spruit to procure the necessary 

 power to operate the machinery. But towards the middle of 1887, 

 the discoveries on the Witwatersrand became so promising that 

 mills driven by steam power began to be more common. These 

 mills were built by Sandycroft and had stamps 750 lbs. weight. 

 Xo ore feeders were used, nor stone crushers. At this period the 

 only American-made mill was at Lisbon-Berlyn, and out of 60 

 stamps supplied only 10 were erected on this mine. The mill 

 was a knee-framed battery of 920 lb. stamps, and was fitted 

 with the Hendy ore feeder. The ore in this case was broken pre- 

 liminariry with Blake crushers. The chief defect in this mill was 

 that the mortars were made in sections' for convenience of trans- 

 port, these being in five sections, tied together with longitudinal 

 bolts, the housings being made of cast iron on the front and back 

 and steel plates on the ends. The housings were secured to 

 flanges on the cast iron bottoms by rivets and bolts. This mill 

 was driven by a Pelton wheel under a head of 1,000 feet. The 

 adjacent mine, Graskop, was equipped with 20 stamps of 850 lbs. 

 The mill was made by Sandycroft, but the framework was of the 

 American type, and the mill was fitted with automatic feeders and 

 stone breakers. This was also a water power driven mill. During 

 1887, Knights Company, now known as the Witwatersrand G.M. 

 Company, entered into a contract with Robey & Co. for a com- 

 plete mill of 100 stamps, with Jordan's concentrators. This mill 

 was built in four groups of 25 stamps on one cam shaft, the cam 

 shafts being made in two sections, 15 stamps on one section and 

 10 on another, both coupled with solid flanged couplings and 

 turned bolts. Each group of 25 stamps was driven from a flywheel 

 and 2oin. belt on the extreme ends of the crank shafts of a 

 2-coupled simple Robey non-condensing engine, with cylinders 

 I Gin. by 32in. Steam was supplied by four Robey loco, type 

 boilers of 25 Nom. H.P. Nearly all the mortar boxes broke 

 within a few months' time, and were replaced bv Sandycroft 

 mortars. The Jordan concentrators were a failure from the start. 

 Very little crushing, comparatively speaking, was done by this 

 mill, that boasted a good mill site on the side of the hill, an 

 unusual thing then. 



The first American mills erected on the Witwatersrand Gold 

 Fields were the 20-stamp mill at the Bantjes, originally ordered 



