SOME NOTES IX REFERENCE TO THE MACHINERY IN 



USE IN THE TRANSVAAL SHORTLY AFTER THE 



RETROCESSION OF THE COUNTRY TO 



THE BRITISH. 



By Harry W. Miller, A.M.I.C.E. 



When the writer entered the Transvaal at the beginning of 

 1883, there was very httle mining carried on except some alluvial 

 washing at Pilgrim's Rest, for which no machinery was required. 

 Some of the quartz outcrops in that district were being investi- 

 gated, and a few mills were designed to deal with these reefs, 

 and later on were built and for a brief period worked. In that 

 year there were two manufacturing concerns under construction, 

 the Hatherley Distillery and the Gunpowder Works, At the 

 former, steam was supplied for distillation and power by two 

 compound boilers made in Germany, the lower portion being a 

 cylindrical boiler with a large flue tube, surmounted by a similar 

 boiler with a number of small tubes running through it. The fuel 

 obtainable then was only inferior grade bush timber, so to obtain 

 a sufficient grate area, a furnace or fire box was built outside of, 

 and adjacent to, the flue of the lower boiler, and the result was a 

 considerable loss of heat by radiation, and, at a later period, when 

 coal was procurable, the furnaces were altered to permit of firing 

 in the flue tube at the suggestion of the writer, with resultant 

 economy. The driving motor was a horizontal engine of about 

 30 brake h.p. This Company was the possessor of the only lathe 

 and drilling machine operated by power at that time in the Trans- 

 vaal. It is interesting to remark here that the lathe was largely 

 employed turning down shells for a 7-pounder cannon that the 

 Boers had captured from the British, and which formed a large 

 proportion of their then supply of artillery. The remaining plant 

 of this company consisted of a portable Robey engine, that drove 

 the circular saw employed for cutting up the bush timber for fuel, 

 and a Robey portable pumping engine, which was seldom used. 



The Gunpowder Works was equipped with a boiler of the 

 Elephant type, made by Halls of Dartford, a type of boiler much 

 affected in explosive works on account of its safety from explosion 

 when the feed water got below the normal level. This class of 

 boiler is obsolete to-day, as it is very troublesome to set, and, if 

 any bricks become dislodged in the arch over the lower tubes, its 

 draught efficiency is much impaired. It was, however, well 

 adapted for the inferior fuel we had to use then, having a large 

 grate area, and even when coal was obtainable later, it gave good 

 results with the inferior coal first mined in the Transvaal. It 

 supplied steam at a pressure of 60 lbs. to a i4in. bv 24in. hori- 

 zontal engine, developing about 45 I. H.P. The other steam 

 power on the property consisted of a 10 Norn. H.P. Hornsby 

 semi-portable engine and boiler with the engine mounted on the 

 top of the boiler. This engine also drove the circular saw for 



