Identifier: sciencerecordcom1874beac (find matches)
Title: The Science record; a compendium of scientific progress and discovery
Year: 1872 (1870s)
Authors: Beach, Alfred Ely, 1826-1896
Subjects: Technology Industrial arts
Publisher: New York, Munn
Contributing Library: Smithsonian Libraries
Digitizing Sponsor: Smithsonian Libraries

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ALOGY. 535 THE DIAMOND MINES OF AFRICA. As far as one can see within the camp, there is but asuccession of pits and mounds mainly occupied by workersbusily intent on finding the precious gem. The perseve-rance and temper of the drifted diggers are shown by thedepth of their deserted pits; some are but three or fourfeet deep, some forty. At the bottom of the working pits are naked Kaffirs dig-ging and throwing up the earth ; others carry it to thebaas, who, perched high on the upturned soil, is busilyengaged in sifting or sorting the gravel. The claims are limited to thirty feet square, for which alicense fee of ten shillings a month is exacted. As thereis no opportunity to castaway the upturned earth and sur-plus gravel—no space being left for roads, and encroach-ments on neighboring claims being punishable by a finefixed by the committee—all the earth must be handled onones own claim. The usual plan is to work out half theclaim, piling the sorted gravel on the other, then fill up
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SIFTING THE GRAVEL. 536 SCIENCE RECORD. the hole, and proceed with the remainder of the claim inthe same way. For sifting the gravel, an apparatus is prepared in thiswise : two posts about seven feet long are driven into theground, four feet apart, and across them ropes are looselyfastened so as to hang in an ample curve. On these ropesare suspended two large sieves of wire or perforated metal.The soil is thrown into the upper and coarser sieve, andthe sieves are shaken to and fro. The larger stones stopat the top, the gravel is retained by the liner sieve, thedirt of course passing through to the ground. As the soilis limy and much of it very fine, the dust is terrific, thecamp being usually enveloped in a cloud of this irritatingeye and lung destroying substance, which is so penetratingthat the best hunting watches are clogged up with it inno time. The editor of the Diamond News classes itwith plague, pestilence, and famine, and if there is anything worse, with that also ; which is

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