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the water. Of course, this slicing in twain of the cradle has been prearranged, the ribs forming the structure being so dovetailed together that they require but the almost instantaneous manipulation of key-pins to disconnect them.
As a final touch in the construction of the raft, bulkheads of heavy timber are placed at either end of the structure; and a six- or eight-inch hawser is attached, by means of which the unwieldy mass is towed out of the river where it was built and along the coast. All the giant rafts thus far built have been constructed at Stella, Washington, or some other point on the Oregon or Washington shore of the Columbia river, and have been towed to San Francisco, where they are broken up and sold, mainly to shipbuilders, for use as spars, or to contractors, for use as piling in railroad construction, etc.
In making the trip down the Columbia river, a giant raft is usually towed by a powerful tug, with a stern-wheel steamer at the after end of the log mass, for steering purposes; for this waterway is shoal in many places, and a raft drawing 2212 feet of water is likely to go aground unless guided with great care. For the
ocean voyage, the raft is usually taken in tow by two big tugs. For the journey from San Francisco to Shanghai with the pioneer trans-oceanic raft, it is proposed that the two tugboats shall be accompanied by a collier or oil steamer carrying fuel for the little fleet, which could also assist in the towing if necessary.
Considering the number of rafts which have been built, and the severity of the storms encountered on the misnamed Pacific, there has been a surprisingly small percentage of loss in transporting logs by this method. To be sure, one or two of the earlier rafts launched on the Pacific by Mr. Robertson did break away and go to pieces, stray logs being cast up as far away as the shores of Hawaii and Mexico; but latterly, practically no losses have been sustained.
For all that, marine underwriters look upon the log rafts as rather undesirable risks; so much so that they usually charge premiums of ten per cent or more for insuring these craft. The consequence is that the raft companies seldom if ever insure a raft for more than onethird of its value. They insure merely to the extent of guaranteeing reimburse
ment for the actual cost of constructing raft of sawed material was constructed the raft, and without reference to the at Portland, Oregon, the component probable selling price, which in most in- parts being held in place by a rather elabstances includes a profit of $20,000 or orate steel framework; but when a storm more-a margin of gain that explains was encountered, the immense mass went why great risks are taken in shipping to pieces in short order, and no effort has spars and piling by means of rafts. been made to repeat the experiment. This
In raft construction, as in regular ship- mishap, and the occasional loss of a log building, there is a constant tendency to- raft in the early days, laid the foundation ward increase in size. The earlier rafts of a spirit of opposition, and certain shipdid not exceed 300 feet in length, a rep- ping men are yet loud in their denunciaresentative raft of that period contain- tion of the giant rafts as menaces to naving 450,000 linear feet of piling and spar igation. timbers, valued at $45,000. One of the In explanation of the demand for the most recent of the giant log rafts was red and yellow firs of the Northwest, it over 700 feet long and 50 feet wide; was may be noted that these trees rival pine in bound together by 120 tons of iron chain, lightness, and oak in strength and dura: and contained 600,000 linear feet of pil- bility. They have nearly twice the ing, equivalent to 8,000,000 feet of lum- strength under pressure of Eastern oaks, ber, board measure. And now it is an and nearly three times that of pine. nounced that the raft which is to be sent Moreover, they grow very straight. Shipto the Orient will contain no less than builders universally recognize the wonten million feet of lumber.
derful durability of these firs; and it is The success of log rafting on a colos- claimed that, until the steel mast was insal scale on the Pacific, is in marked con- vented, no yacht ever defended the trast to the failure that has attended ef- America's Cup that did not shake her forts to raft sawed lumber by the same sails to the breeze from sticks that came method. Several years ago, an immense from the forests of the Northwest.