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and other interior States, Dr. David T. assay value of $1,000 per ton in gold and Day, Chief of the Division of Mines of platinum alone, while in other cases it the Geological Survey, established at was demonstrated that, though the sand Portland, Oregon, an experiment station, could not profitably be handled for any where, with an equipment comprising all single component part, it was well worth the various types of machines that could treatment if arrangements were made to possibly be of use in such work, he and save all the different mineral substances his assistants have been testing the vari- it contained. In other words some deous samples and evolving the best and posits are not rich enough in either gold most practical methods of handling such or platinum to make it pay to work them, material. The experiment station was but, if the magnetite, chromite, garnet, first established early in the summer of monozite and quartz which they yield are 1905 and the work is still actively in also conserved, the net result is to make progress.
the venture a highly profitable one. From the very outset the results were Dr. Day and his assistants have acboth gratifying and surprising. The complished such wonders on the Pacific government investigators not only found Coast that the government has hastened platinum in quantities that exceeded their to broaden the scope of the work and an expectations, but they discovered that the experiment station has been established black sand or sediment was rich in many at Chapel Hill, N. C., for the treatment other valuable substances, notably gold. of the low-grade gold deposits of the In some instances it was evident that a mid-Atlantic and Southern States. Angiven deposit was well worthy of treat- other experimental plant or "concentratment merely for the extraction of one or ing pavilion” will be installed at the two minerals, as, for instance, a large coming Jamestown Exposition in order shipment of the sand from Humboldt that the public may be treated to practical County, California, which showed an object lessons regarding the fruitful new method of utilizing supposedly useless through a magnetic separator, where the deposits.
magnetic elements are extracted. The process followed in the extraction The concentrators which play so imof the mineral wealth is the same, in the portant a part in this ingenious new case of all deposits of sediment or black method of mining may be popularly desand handled at the government experi- scribed as quivering tables, oblong or cirmental plants. The sand first enters a cular in form, over which there pours "feeder," after which it is elevated by a perpetually a stream of water. The surbelt conveyor and delivered to a screen. face of the table is covered with grooves Next the material passes to a revolving, or corrugations of rubber or metal. When mixing, distributor, from which it is the gold bearing sand is placed upon a piped to the different concentrators. concentrating table the rush of water This method insures an even quality of carries off the clay and other worthless pulp for all concentrating machines. material while the particles of mineral, After passing over one or another of the being heavier, sink to the bottom and concentrating tables the material for ex- lodge in the riffles. The constant tremamination is placed in a drying furnace, bling of the table serves to concentrate where all the moisture is expelled. The these mineral particles and bring them to pulp, when thoroughly dried, passes a common point of discharge.
Song of the Engine
'LL sirg you an engine's song; I am the master of all
Yet I was planned by the hand of man, molded and reared by him.
Mine is a song of pleasure,
For sweet is the wage I earn,
I am the force of the world ; its wheels are as children's toys,
For I with my strength can move them all at the touch of a lever bar;
And sweet is the song I sing,
For I sing that man may live,
That my children's voices give.
Master of man am 1-yet I hark to his every word
Giving the soul of my life to him in his endless quest for gold;
Giving my strength, my life,
To man in his quest for gold;
THE MILWAUKEE SENTINEL.
VIEW OF SAN PEDRO BREAKWATER FROM SHORE END.
T San Pedro, thirty miles south region, can be brought by water far of Los Angeles, California, a cheaper than by rail. San Pedro had great stone breakwater, more only limited wharfage, and absolutely no
than a mile and a half long, is sheltered anchorage; but, like many enbeing built out into the Pacific Ocean. gineering projects of great magnitude, a It will cost nearly three millions of dol- breakwater was considered impossible or lars—furnished by the national govern- impracticable until it became a necessity. ment-and, when it is completed, the Congress discovered in this situation only safe and commodious harbor be- a real need for its assistance, and detween San Francisco and the Mexican cided to build a government breakwater border, a distance of 500 miles, will be as the starting point for the making of ready to handle the great traffic of the a great seaport. After long delays, a rapidly developing Southwest. Already contract for the construction of the a new transcontinental railroad has made breakwater
to a Chicago its terminus at Los Angeles and the port contracting firm. The contract called of San Pedro is almost certain to become for a V-shaped structure 8,500 feet one of the great natural gateways to the long, to be built of granite and Orient, while lumber and other products sandstone. The agreement specified that of the north will be brought to its docks for the substructure that part of the in huge quantities.
structure below low-water line), oneSan Pedro has long been an important third of the rock must be of a size rangseaport of the Pacific coast ; but of late ing from 100 to 1,000 lbs.' weight; oneyears its steadily growing lumber trade third must weigh between 1,000 and has been seriously hampered by a lack 4,000 lbs.; and the remaining third must of ample sheltered anchorage. The rapid be stones of a weight exceeding 4,000 development of Los Angeles and the ad
lbs. In the superstructure (that part of joining country has created a great de- the structure above low-water which is mand for lumber; and this lumber, which set carefully in tiers), no stone could be is obtained chiefly from the Puget Sound placed on the harbor side of less than 3 tons' weight; and on the sea side, no $0.84 per ton for the substructure, and stone weighing less than 8 tons. The $3.10 per ton for the superstructure. The contractors agreed to furnish, and to put granite is, however, of a better quality in, the rock of the substructure, for than that used before. It comes by rail $0.5472 per ton, and that of the super- from Casa Blanca, Riverside county, 100 structure for $0.72 per ton.
miles from the site of the breakwater. San Pedro was jubilant over the first At the quarries the rock is loaded on step toward the realization of her hopes; standard flat cars, which are hauled dieveryone knew the details of the contract, rectly out onto the trestle at San Pedro. and the preparations for bringing the Here the heavier pieces are handled by first rock were watched with interest. cranes. The cranes are merely very Buoys were anchored at intervals along large, 90-horse-power steam shovels, with
the line of the breakwater; and on April specially rigged booms and hoisting 27, 1899, the first barge of rock from tackle substituted for the shovels. The Catalina Island, twenty-seven miles to rock for the substructure is swung out the southwest, made fast to a buoy and over the water, and, when the boom is in dumped its cargo. Things worked well the desired position, the stone is released for a time, and soon 80,000 tons had been by means of a trip chain. The regular deposited. Then the contractors were shaped blocks used in the superstructure unable to get the rock out as fast as be- are carefully placed and fitted. fore, and there was trouble ahead. After The building of the superstructure is some parleying, the contract was de- by far the most interesting feature of the clared forfeited in March, 1900.
work. A section of the top of the subThis was, of course, a damper on the structure is first brought carefully to the bright prospects that had encouraged required level (mean low-water mark), San Pedro; but in June, 1900, the con- and then a monster block of granite tract was relet to the California Con- weighing from 8 to 25 tons is lifted by struction Company, and work on the the powerful arm of the crane and lowbreakwater was resumed. By the new ered into place. The stone is first placed contract, the Government was charged in its approximate position to see how it
fits. If it does not rest quite level or is tide. The men must work in one or two a trifle too high or low, it is raised again, feet of water part of the time, and even and the smaller stones of its bed are re- in the mildest weather they are frequentarranged. A ponderous block may thus ly drenched by a playful wave. Then, be placed three or four times before it is too, there is considerable danger from left in its final position. The elevation broken chains and falling stones, so that of the stringer along the trestle is used as on the whole it is rather difficult to keep a datum plane, and, by means of a meas- a full gang of men.
But the present uring pole lowered from above as each contractors seem to know how to hanstone is placed, the upper surface of a dle these matters, and in spite of tier is kept level and regular. The stones many difficulties the breakwater is steadof the bottom tier on the sea side can be ily growing. placed only during calm weather at low As the massive walls of the super