Electric lights are used throughout the mines, and underground work is carried on both day and night by three shifts. Every known scientific device is pressed into service. In all of the deep mines the laborers are taken up and down the shafts in cages.
The method of mining and working the diamond-bearing earth at present employed is far more economical than in former years. After the blue material has been brought up it is carried to the depositing floors where it is allowed to remain several months. In the meanwhile it is harrowed several times to break the lumps. The part that resists this treatment is carried to a mill to be crushed. The disintegrated and pulverized material is then carried to the washing machines.
The coa.r.s.er fragments of the concentrates from the washing machines are picked out by hand; the finer are sent to the pulsators. Each shaking-table of the pulsators is made of corrugated iron plates in several sections with a drop of about an inch from one division to another.
A sufficient quant.i.ty of thick grease is spread over the plates to cover them to the top of the corrugations. The concentrates are continuously spread over the upper portion of the table automatically while running water washes them down.
Strange as it may seem, the diamonds stick fast to the grease; the other material is washed away. It has been found by trial that grease will cling to the precious stones but to nothing else. After a few hours the grease with the diamonds is sc.r.a.ped off the tables and steamed in perforated vessels to separate them.
[Ill.u.s.tration: Sorting gravel for diamonds in the Kimberley mine]
One of the De Beers mines has been worked to a depth of about two thousand feet with no diminution in the quant.i.ty or quality of the diamonds. The "pipe" or plug of blue-stuff shows no signs of giving out.
Nature, in her underground laboratory, works in a mysterious way, baffling the astutest students of science to find the process by which she is able to manufacture such beautiful gems as the diamond. Many theories have been propounded to explain the genesis of the diamond, the most plausible one being that the crystallization of the carbon is due to a very high temperature and tremendous pressure acting on the carbon in a liquid form deep down beneath the earth"s surface. The crystals, intermingled with much foreign matter, are afterward projected upward, filling these great volcanic pipes.
In order to produce the most beautiful effect, diamonds are usually cut into one or another of three different forms, namely, rose, table, and brilliant, the shape and size of the stone determining which form is best. The double-cut brilliant is the most common form at the present day. The general form of rough, crystallized diamonds is that of two square pyramids joined at their bases. The crystals are oftenest found octahedral and dodecahedral--that is, eight and twelve sided, and the diamond-cutter takes advantage of these forms in shaping the diamond.
The modern lapidary must have a perfect knowledge of optics and be a skilful stone-cutter. The numerous planes or faces which he cuts on the surface of the diamond are called facets. In the treatment three distinct processes are utilized--cleaving, cutting, and polishing. The lapidary must study the individual character of each stone and determine whether to cleave or grind off the superfluous matter so as to correct flaws and imperfections. All this calls for the judgment which comes only with long experience, for if the cutter errs he may ruin a priceless gem.
The grinding and polishing are done by diamond dust mixed with oil spread on the upper surface of a grooved flat steel wheel revolving horizontally. The diamond, having been set in fusible solder, is firmly pressed against the surface of the wheel by a small projecting arm and clamp. When one facet has been finished, the diamond is removed from the solder and reset for grinding another facet. Thus the workman continues until the grinding and polishing are completed. Infinite patience and steadiness of nerve, as well as steadiness of hand, are required for such delicate and exact work. Sometimes two uncut stones are cemented into the ends of two sticks. Then the operator, using these sticks as handles, presses the stones against each other with a rubbing motion, the surface of the stones being coated over with diamond dust and oil to accelerate the process.
The last cutting of the celebrated Kohinoor diamond cost forty thousand dollars. One may understand, therefore, that the expense of cutting a large diamond adds materially to its cost. The diamond-cutting industry is confined chiefly to Amsterdam, where the work employs several thousand persons, mostly Hebrews, the craft having been handed down from father to son through several generations. Much fine cutting is now done in New York also.
FOOTNOTES:
[Footnote 4: The term pan is a name applied to a basin or pool in which water collects during the rainy season.]
[Footnote 5: Fontein is a word of Dutch origin meaning fountain or spring. In this hot and semi-arid country a pan or fontein was a necessity to the Boer farmer, whose chief dependence was on his sheep and cattle. Hence he was wont to settle near where water could be easily obtained.]
PART II
OCEANIA
CHAPTER XXII
THE ISLANDS OF THE PACIFIC
Not until four hundred years ago did the body of water now named the Pacific Ocean become known to the people of Europe.
A vague knowledge of a sea that washed the eastern sh.o.r.es of Cathay, or China, was gained from the reports of the famous Venetian traveller, Marco Polo. After spending several years in the Orient, Polo returned home in 1295, giving such marvellous accounts of the countries visited and things seen that his stories were but half believed.
In 1531, Balboa, a Spanish explorer stationed at Darien, now Colon, hearing rumors that a great ocean lay to the opposite side, determined to test the truth of the report. Taking with him about three hundred men, he laboriously worked his way through the jungles of the isthmus; and on reaching the top of the divide beheld for the first time the Pacific Ocean. He then hastened forward, and as he reached the sh.o.r.e he waded into the water and took possession of it in the name of his sovereign. He named it the South Sea.
But the vast extent of this sheet of water did not become well known until fifty years later, when brave Ferdinand Magellan circ.u.mnavigated the globe. Two and one-half centuries more elapsed before the memorable voyages and discoveries of Captain Cook disclosed the fact that the new ocean world was studded with countless islands, and that most of them were densely inhabited by savages.
Just how or when all these islands became inhabited is not definitely known. Since the Polynesian languages in general are similar, it is conjectured that the inhabitants of the islands have a common origin and that many of the more northerly groups were peopled by emigrants from the south.
In a general way the name Oceania is applied to all of the islands in the Pacific, but in a more limited sense only to those lying between the American continent and Australasia.
The chief divisions of Oceania are Australasia, Melanesia, Micronesia, and Polynesia. Australia, the largest body of land, is usually regarded as a continent. Nearly all the smaller islands are of coral or of volcanic origin; in many instances both agencies have contributed to their formation. The coral and volcanic islands seem to be the tops of mountain ranges that, little by little, have sunk, until only their higher summits are now above sea level.
The central part of the Pacific Ocean is pre-eminently the home of the reef-building coral. Countless islands and reefs, wholly or partly built up by these tiny creatures, are found widely scattered over an immense area limited to one thousand eight hundred miles on each side of the equator. All these formations are composed of the compact limestone remains of coral polyps.
These polyps have the power of extracting carbonate of lime from the sea-water and building it into ma.s.sive formations which, for the most part, are nearly or completely submerged.
The reef-building coral differs very materially in form and appearance from the precious or red coral; the former is confined to comparatively shallow water, while the latter is found most commonly at a depth of six hundred feet or more, and it occurs chiefly in the Mediterranean Sea. The common or reef-building coral has but little use except as a source of lime, and no intrinsic value except as an object of curiosity.
Coral reefs may be arranged under three cla.s.ses; namely, fringing reefs, barrier reefs, and atolls. The first cla.s.s embraces the shallow-water reefs found close to land, either surrounding islands or skirting the sh.o.r.es of continents. The reefs of the second cla.s.s likewise skirt islands or continents, but at such distances as to leave a deep channel between them and the sh.o.r.e. The third cla.s.s are called atolls; each is irregularly ring-shaped and almost entirely encloses a sheet of water, called a lagoon.
The ring-shaped reef, or atoll, is broken in one or more places, generally on the leeward side, and built up higher on the windward side.
The reason for such omissions and buildings is obvious when we remember that the coral animal cannot move from its fixed position to seek food, but must depend upon the waves to bring it within reach. The water dashing up against the reef on the windward side brings an abundance of food, while the slight movement of the waves on the leeward side brings but little food.
After many years the dead coral is broken off and piled up on the reef.
In this condition it is cemented by the lime in the sea-water, thereby forming a nucleus for land. Then, perchance, a cocoanut drifts upon the formation and, finding sufficient nutriment, sends down a root and begins its growth. Other cocoanuts are drifted to the newly disintegrated coral soil until the tropical vegetation becomes capable of sustaining animal life. Or, perhaps, a portion of the ocean bed in that particular region is uplifted by the volcanic forces, thus greatly enlarging the land area. Attracted by the new land, people from near-by islands emigrate and take possession of the unoccupied area. Thus the upbuilding of islands and their occupancy goes on through the centuries.
From the fact that these formations exist at a depth of several thousand feet, while coral polyps themselves can live only near the surface, it is thought that either the sea bottom must have been sinking for a long period of time or else that the cinder cones around which the reefs are built must have shrunk away until their tops are below sea level. At all events they seem to be due to volcanic movement.
[Ill.u.s.tration: A Malay girl]
Differences in environment produce marked differences on people in various parts of the continental world. Likewise, differences in the geological structure of the islands of the Pacific have produced a marked influence on the inhabitants of the islands of the Pacific. Those living on large and mountainous islands, where the productions are varied and abundant, are greatly superior mentally and physically to those inhabiting the small low-lying coral islands.
In the small islands, where there are few objects of interest and the circle of life is necessarily circ.u.mscribed and food and building material scanty, the inhabitants are dwarfed in intellect and their languages limited in vocabulary. The inhabitants of the extensive Paumoto group of islands give a striking example of the dreary monotony of life on small coral islands. Indeed, coral atolls are lacking in pretty nearly all the features that are necessary for a high degree of civilization; nature, therefore, reacts, with the result that the human life of this region is in a condition of savagery. Many of the natives are cannibals.
The natives of Australia are a race that seems to be separate and distinct in itself. Wherever they are found their speech and customs are so nearly alike that little or no doubt of their common origin exists.
They are so small in stature that by some scholars they are cla.s.sed with pygmy peoples. They are repulsive in appearance in their native state, but when the children are trained by English families they become attractive. They are regarded as a very low type of intellect; yet at the missionary schools the children seem to learn about as quickly as do European children. The children learn to figure readily, but the older natives have no names for numbers greater than three or four.
In New Guinea and the adjacent islands is found a race of black peoples usually called Negritos, or Negroids. They are black and, like the African negroes, have black, kinky hair. They are far superior to the native Australians. Many of the tribes are good farmers, and cultivate crops of sago, maize, and tobacco. On the coasts there are good boat-builders and sailors. The greater part of the Melanesian tribes is hostile and blood-thirsty; head-hunting is a common practice. In many tribes the people live in communal houses like those of the Pueblo Indians of America.
A large part of the population of Oceania is of Malay origin. As a rule the Malaysians are intelligent and take readily to western civilization.
They are confined chiefly to the larger islands south and west of the Asian continent. In such parts of Malaysia as have become European possessions, they are farm laborers, and in this employment they have no superiors.
[Ill.u.s.tration: A Malay boy]
Of all the native peoples of Oceania, the Polynesians are perhaps the most interesting. In physical appearance they are tall, well-formed, dark of complexion, and black-haired. In the northern island groups--Tonga, Hawaii, Samoa, Tahiti, and others--which are colonized by European and American peoples, the natives have gradually acquired western civilization. The number of natives has decreased, however, and only about one-third of the population of fifty years ago remains to-day.
The animal and vegetable life is peculiar. That of Australia resembles the life forms of a geological age long since past; that of the islands near tropical Asia is Asian in character. Now there are many large islands at a considerable distance from the continent in which many of the life forms on the slopes facing Australia are Australian, while on the northerly and westerly slopes they are Asian. One cannot be certain, however, that these islands were ever a part of the Australian continent, or that they were ever joined to Asia. On the contrary it is more probable that the life in question was carried by winds and currents of the sea.
The life forms of the coral atolls are very few in number. So far as vegetation is concerned, the cocoa-palm and breadfruit are about the only kinds of plant life of importance. A few species of fish and migratory birds are the only animals that may be used as food.
The names given to the various divisions of Oceania are more or less fanciful. Australasia means Southern Asia; Malaysia, Malayan Asia; Melanesia, the islands of the blacks; Micronesia, small islands; and Polynesia, many islands.
During the latter half of the nineteenth century practically all of Oceania has been divided among European powers. Australia, Tasmania, and New Zealand are peopled by colonists from England; but they possess the character of a great nation rather than that of colonies. A few of the larger islands have become producers of sugar, cotton, and fruit. The long distance from the markets for their products is offset by the low cost of native labor. The coral islands are almost valueless for commercial products; but a few of them are used as coaling stations, telegraphic cable stations, or as positions of naval advantage.