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by surface drainage after heavy rains, and sometimes covers fifty or sixty acres, when good boating and wild-duck shooting may be had upon it, but in times of drought it is entirely dry. The water of the pan, and of another body, Blankenberg's Vley, is leased by the diggers for mining purposes. Except that it is semicircular instead of being circular or oval, the description of the Dutoitspan is very similar to that of the other mines.

The gems were extracted from the earth, at the beginning, when everything was crude and done in haste, and when water was scarce, by the method of "dry-sorting," which consisted in sifting the excavated ground through hand-sieves, and then passing the finer portions over a sorting-table. By this method as many diamonds were missed as were found, and frequently the yield from the rewashing of the earth over which the process had been performed gave better returns than were gained in the first instance. A modification of the "cradle" was then introduced, but it eventually gave way to the "Rotary Washing-Machine," which is still generally employed. It consists. of an annular-shaped pan, from eight to fourteen feet in diameter, which is closed by an outer and an inner rim, of which the inner rim is about four feet in diameter, and is not so high as the outer rim. A vertical shaft rotates in the center of the open space, carrying ten arms radiating around it, each of which has half a dozen vertical knives, or teeth, set within half an inch of scraping the bottom of the pan. The diamondiferous ground, mixed with water, enters through an orifice in the outer rim of the pan, and is stirred up into a ripple by the revolving knives, whereby the lighter stuff comes to the surface and continually floats away through an orifice in the inner rim, while the heavier gravel falls to the bottom of the pan. The mud, or "tailings," which flows to waste over the inner rim, is led by a shoot to a pit, whence it is lifted by a chain and bucket elevator some twenty or thirty feet high. At the top of the elevator the buckets deliver the tailings onto suitable screens, over which the solid mud runs to waste, while the muddy water is led back by an overhead shoot to the machine to assist in forming a puddle of sufficient consistency to float the lighter stones in the pan, and allow only the heaviest ground to accumulate at the bottom. For the better mixing of this puddle, an inclined cylindrical screen is fixed above the level of the pan. The dry ground from the mine is tipped into the upper end of the screen, where it is met by the muddy water from the elevator and a certain amount of clear water. The large stones, of a size unlikely to include diamonds, roll out at the lower end of the cylinder, but the puddle, carrying all the smaller stones with it, passes through the wire netting of the screen and down. a shoot into the pan, as above described. At the end of the day's work the machine is stopped, and the contents of the pan, after they have undergone an intermediate cleaning in a cradle, or in a small gravitating machine, called a "pulsator," are emptied upon the sort

ing-table. The "pulsator" is also often so employed as to dispense with the "panning" process.

At the "river-diggings" (on the Vaal) the diamondiferous deposit is imbedded between bowlders and mixed with fine red sand, and sometimes with lime. The diamonds are separated by sifting the earth through a machine called a "baby"-a kind of swinging sieve, which, the coarser pebbles having been taken out by another sieve impending above it, allows the medium-sized pebbles, supposed to contain diamonds, to roll into a tub, while the finer refuse sand passes through its meshes. The contents of the tub are then gravitated, and the heavier stones are turned upon a "sorting-table," and the diamonds picked out by careful scraping. An experienced digger can tell at a glance, from the appearance of the deposit, what chance there is of "finding well" in it. He knows by sight the heavier stones that occur in diamond-bearing ground, and their presence is a sure sign of diamonds being there too. This is particularly the case with a curiously marked pebble that is streaked with a succession of parallel rings, from which it has received the descriptive name of "banddoom" (bandround). The specific gravity of the "banddoom" is almost identical with that of the diamond, and, where the former is found, experience has taught that the latter may be confidently expected. Beautiful agates are also found in this deposit, as well as quartz-crystals, jaspers, chalcedony, but few garnets, and no iron pyrites or carbon, which occur so plentifully in the Kimberley mines. An assortment of "river-stones" forms a very pretty collection, and it is conceivable enough that, prior to the opening of the diggings, diamonds should have been picked up by the natives and valued as more than ordinarily pretty pebbles. The river-digging is, however, not very profitable in the face of the large returns given by the Kimberley mines, and is now relatively of but little importance.

The whole number of claims in the four mines of Kimberley and Beaconsfield is 3,238, covering about seventy acres of diamondiferous gravel. The whole property is assessed at £5,172,975, or at the rate of £75,000 per acre, and is divided among ninety-eight holders, forty-two of whom are joint-stock companies, and the remaining fifty-six private firms and individuals. The gross capital of the joint-stock companies, which hold 2,211 claims, is returned at £7,970,490; and that of the private holders is estimated at £1,624,900, making the gross capital of the entire mines £9,595,390. The annual expenditure in labor, material, etc., is not less than two million sterling, or ten million dollars. It has been estimated, by the comparison of information from various official sources, that the gross value of diamonds exported from the Cape Colony up to the end of 1885, exclusive of such as were not reported or were illicitly taken away, amounted to £35,000,000. The total yield of diamonds from the Vaal River to date has probably exceeded £2,000,000.

In quality the Vaal River stones are rated highest, in the degree that while in the three years ending with August, 1885, the weight of those sent away from that district was only about, that of the entire exports their declared value was as much as of the total value exported. Of the four Kimberley and Beaconsfield mines, Dutoitspan produces the finest stones, ninety per cent being perfect. Bultfontein comes next, with its beautiful white stones, weighing from a quarter of a carat to two carats. De Beer's comes next, and Kimberley last. In absolute value of production, the order is, Dutoitspan, De Beer's, Kimberley, Bultfontein. The largest diamond ever found in Griqualand West was an irregular octahedron from Dutoitspan, slightly spotted, and of yellow color, which weighed 404 carats, or nearly three ounces. The only larger stone than this known to have ever been found was a very imperfect one, discovered near Jagersfontein, which weighed about 500 carats. Another diamond, of 352 carats, has been found at Dutoitspan. The largest stone ever found at Bultfontein weighed a little more than 150 carats. The Bultfontein diamonds, while superior in color to all others except those of Jagersfontein, are of smaller average size than those of the other three mines.

All the diamonds coming from the various South-African mines. are said to have a distinct personality, by means of which experts can at once recognize stones from either of the four mines, and tell from which it came, and can again distinguish those of the Kimberley and Beaconsfield mines from those of the river-diggings, and their testimony on this point is accepted by the courts.

All the theories by which the attempt is made to account for these mines recognize them as of volcanic origin. Their form suggests at once the crater of an extinct volcano, or the tube of a geyser. When the attempted explanation goes beyond this, the range of diverging opinions is quite wide. Of these various views, we will refer only to the observation of Sir Henry Roscoe, that the most noteworthy feature of the diamond-bearing rocks of Kimberley is the discovery in the diamond-earth of a volatile crystalline hydrocarbon, soluble in ether, which seems to confirm the hypothesis that the carboniferous shales, which are penetrated by the diamond-bearing pipes, have been the source of the carbon now found in the crystalline state in this gem. The physical structure of the ash, or incombustible portion of the stone, is of a very singular character, and has hitherto not been examined. A careful study of it may possibly throw light on the important question of the mode of formation of the diamond.

66

"W 'Wo

MATERIALISM AND MORALITY.

Br W. S. LILLY.

WORDS are grown so false that I am loath to prove reason with them," says Viola in "Twelfth Night." The saying constantly comes to my mind in dealing with the philosophical controversies of the present day. Rigorous definition, careful analysis, precise classification, are no longer in favor. It is an age of loose thinking, and of looser writing; of "idle words, servants to shallow fools." Never, perhaps, was there an age in which the trade of the sophist, whose business it is "to make the worse reason appear the better," was carried on so successfully. Never was there an age in which a writer who feels that he is "a teacher, or nothing," had greater need of well-considered and accurate language. Hence it is that in the papers which I have from time to time contributed to this "Review" I have sought, before entering upon my argument, to state clearly the sense in which I employ my principal terms. Most necessary is it that I should do this in respect of such a word as materialism. There are those who would restrict it to a doctrine which is now discredited for higher minds. What we know of living forces, of the real properties of bodies, has made an end of the old notion of matter reduced merely to solidity and extension. Our better acquaintance with the physiology of the sense-organs has been fatal to the sensism which Professor Clifford contemptuously calls "the crass materialism of the savage." It lingers, indeed, in the lower intellectual regions. Nay, more, it is still widely held there. "Il y a des morts qu'il faut tuer encore." And this is one of them. My present point, however, is that this coarse and vulgar theory is by no means the only form of materialism. Nor is it the form under which materialism is most potently working in the world just now. The more subtile doctrines. which have arisen upon the ruins of the old materialistic hypothesis are, in all essentials, identical with it. Positivism, determinism, and much that passes current as agnosticism, are mere varieties of materialism; sublimated expressions of it, perhaps, but true expressions, having in them the root of the matter. Now here I am conscious of a difficulty. Is it fair, one may be asked, to impose the name of materialist upon those who, more or less energetically, repudiate it? I think it is fair, and, more, that it is a duty, if the name truly describes them. Take, for example, the late Mr. Clifford. As we have just seen, he rejects emphatically "the crude materialism of the savage," but only to substitute a materialism which is, indeed, more refined, but which is also, as it seems to me, more irrational. His biographer, Mr. Frederick Pollock, claims that his view is, in truth, "idealistic monism, a very subtile form of idealism," and points out that his con

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