Handwork in Wood. William Noyes
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logs in all directions up-ended. * * *
Then all at once down by the face something crashed, the entire stream became alive. It hissed and roared, it shrieked, groaned, and grumbled. At first slowly, then more rapidly, the very fore-front of the center melted inward and forward and downward, until it caught the fierce rush of the freshet and shot out from under the jam. Far up-stream, bristling and formidable, the tons of logs, grinding savagely together, swept forward. * * *
Then in a manner wonderful to behold, thru the smother of foam and spray, thru the crash and yell of timbers, protesting the flood's hurrying, thru the leap of destruction, the drivers zigzagged calmly and surely to the shore.
Sometimes cables have to be stretched across the chasm, and special rigging devised to let the men down to their dangerous task and more especially to save them from danger when the crash comes.
Fig. 20. Splash-Dam.
Fig. 21. Logs in Boom. Glens Falls, New York.
In case such efforts are unavailing, it is necessary to "shoot" the jam with dynamite. Another device resorted to where the supply of water is insufficient is the splash-dam, Fig. 20. The object is to make the operator independent of freshets, by accumulating a head of water and then, by lifting the gates, creating an artificial freshet, sufficient to float the timber down stream.
Fig. 22. A Sorting Jack.
Thus by one means and another, the logs are driven along until caught by a boom, Fig. 21, which consists of a chain of logs stretched across the river, usually at a mill. Since the river is a common carrier, the drives of a number of logging companies may float into the mill pond together. But each log is stamped on both ends, so that it can be sorted out, Fig. 22, and sent into the boom of its owner.
The operations described above are those common in the lumber regions of the northeast and the Lake States. But special conditions produce special methods. A very effective device where streams are small is the flume, Fig. 23. This is a long wooden trough thru which water is led, and the logs floated end on. It is sometimes many miles long; in one case in California twenty-five miles.
In the South where there is no snow, logs are largely brought out to the railway or river by being hung under immense two-wheeled trucks, called slip-tongue carts, drawn by mules, Fig. 24. The wheels are nearly eight feet in diameter.
Fig. 23. Six Mile Flume. Adirondack Mountains, New York.
Some kinds of wood are so heavy that they will not float at all, and some sink so readily that it does not pay to transport them by river. In such cases temporary railways are usually resorted to.
Fig. 24. Hauling Logs by Mules. Oscilla, Georgia.
On the Pacific coast, where the forests are dense, the trees of enormous size, and no ice road is possible, still other special methods have been devised. On so great a scale are the operations conducted that they may properly be called engineering feats. Consider for a moment the size of the trees: red fir ranges from five to fifteen feet in diameter, is commonly two hundred fifty feet high, and sometimes three hundred twenty-five feet high. The logs are commonly cut twenty-five feet long, and such logs often weigh thirty to forty tons each, and the logs of a single tree may weigh together one hundred fifty tons. The logging of such trees requires special appliances. Until recently all the improved methods were in forms of transportation, the felling still being done by hand with very long saws, Fig. 25, but now even the felling and sawing of logs in the forest is partly done by machinery.
Fig. 25. A Twenty-Five Foot Saw used for Crosscutting Big Logs.
Fig. 26. Hauling Big Logs by Donkey Engine.
To work the saw, power is supplied by a steam or gasoline engine mounted upon a truck which can be taken readily from place to place. As the maximum power required is not over ten-horse-power, the apparatus is so light that it can be moved about easily. The saw can be adjusted to cut horizontally, vertically, or obliquely, and hence is used for sawing into lengths as well as for felling.
Falling beds. Since the weight of a two hundred fifty foot fir is such that if the impact of its fall be not gradually checked the force with which it strikes the ground may split the trunk, a bed for its fall is prepared by the swampers. Usually piles of brush are placed as buffers along the "falling line" so that the trunk will strike these. If the tree stands on the hill side, it is thrown up hill, in order to shorten the fall.
After the felling comes the trimming of branches and knots and "rossing" of bark, to lessen the friction in sliding along the skidway.
The skidway. By the skidway in the Puget Sound region is meant a corduroy road. This is constructed of trunks of trees ranging from a foot to two feet in diameter. These are "rossed," that is, stripped of their bark and laid across the road, where they are held in place by pegs driven into the ground, and by strips spiked upon the tops of the logs. If possible they are laid in swampy places to keep the surface damp and slippery. At turns in the road, pulleys are hung, thru which the hauling cables pass. The skidway runs to the railway siding or water's edge. Over these skidways the logs are hauled out by various means. Formerly "strings" of oxen or Percheron horses were used, but they are now largely superseded by some form of donkey engine, Fig. 26. These are placed at the center of a "yard."
Yarding is the skidding of logs to the railway or water way by means of these donkey engines. Attached to the donkey engine are two drums, one for the direct cable, three-fourths to one inch in diameter and often half a mile long, to haul in the logs, the other for the smaller return cable, twice as long as the direct cable and used to haul back the direct cable. At the upper end of the skidway, when the logs are ready to be taken to the railway or boomed, they are fastened together, end to end, in "turns" of four or more. The direct cable is attached to the front of the "turn", and the return cable to the rear end. By winding the direct cable on its drum, the "turn" is hauled in. The return cable is used to haul back the end of the direct cable, and also, in case of a jam, to pull back and straighten out the turn. Instead of a return cable a horse is often used to haul out the direct cable. Signaling from the upper end of the skidway to the engineer is done by a wire connected to the donkey's whistle, by an electric bell, or by telephone.
Sometimes these donkey engines are in relays, one engine hauling a turn of logs to within reach of the next one, which passes it on to the next until the siding is reached.
Fig. 27. Steam Skidder at Work. Grant County, Arkansas.
Where there are steep canons to be crossed, a wire trolley may be stretched and the great logs carried over suspended from it.
In the South a complicated machine called a steam skidder, Fig. 27, equipped with drums, booms, etc., is much used both for skidding in the logs and then for loading them on the cars. It is itself mounted on a flat car.
An improvement on this is the locomotive boom derrick which is widely used both on the Pacific coast and of late in the Lake Superior region. It is a combined locomotive, skidder and loader. Its most unique feature is that it can be lifted off the track so as to allow flat cars to run underneath it. This feat is accomplished thus: A device, which is something like that used in elevating the bodies of coal wagons, lifts the engine several feet above the rails. Then steel legs, which are curved outwardly, are lowered until the shoes which are attached to them