very extended account of the whole great system of modern engineering appliances in use at the various mines and establishments operated by the De Beers Company in South Africa. This sketch includes not only the diamond mines at and around Kimberlej', but the De Beers Explosive Works, at False Bay, near Cape Town, and other accessory plants. Mr. Allen notes the fact that the last year has witnessed many changes in the work of operating the mines, made necessary to a large extent by the increased depth attained, and he gives first place to the great extent to which electrical machinery has been introduced, not only at the mines but in all the works and holdings of the company. His article, indeed, consists chiefly of descriptions of the electrical apparatus, illustrated by numerous half-tone figures.
The account is a veiy remarkable one in its exhibition of the power and variety of electrical machinery already installed in the vast and varied activities of this immense corporation. To give any particulars in a brief notice like this is of course impossible. The power houses, the various machine shops, and the different kinds of motors employed are all described in some detail and their manner of use in the several parts of the mining and hauling operations. In the machine shops the smaller tools are now for the most part run by separate motors, each motor operating a group of several tools or machines of like character, as lathes, scrapers, screw machines, etc., thus doing away largety with shafting and belting, and resulting in much economy. Powerful narrow-gage electric locomotives are being introduced for ore hauling on inclines, etc., all of which are described and some figured, as are also the elaborate arrangements at the False Bay explosive works.
Mention is made of the fact that African coal is now being freely obtained and is giving much satisfaction. The interruption of this native supply during the late war caused great embarrassment and expense to the De Beers Company, but now the Indwe mines are yielding an output of 12,000 tons per month, of which 5,500 are taken by the De Beers Company. The calorific power of this coal is only about 60 per cent as compared with Welsh coal; but the difference in cost of supply much more than counterbalances this defect. About 1.000 tons a month from the Stormberg district are also used bjT the company.
Mr. Sarrat C. Rudra, a member of the American Institute of Mining Engineers, Calcutta, India, presented at the New York meeting of the Institute, October, 1903, an admirable paper on the mineral resources of India, which treated of the past, the present, and the future possibilities of that great oriental country. Of especial interest are his references to the precious stones.
aTrans. Am. Inst. Min. Eng., New York Meeting, October, 1903, pp. 11-15; Table III, p. 26.