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WHERE THE COPPER RIVER RAILROAD STARTS.
THE TECHNICAL WORLD MAGAZINE
VOL. XVII MARCH. 1912 NO. 1
"IT HAD TO BE DONE"
I ROM the pocket diary of E. C.
JL. Alaska, under date of May 14,
"The falsework under the third span of the bridge was moved out fifteen inches by the ice and had to be put back."
That was all. Even the italics were not in the original entry.
Now that third span of the Miles Glacier bridge was fifty feet long. The falsework consisted of a thousand or two piles, driven deep into the bottom of the Copper River, forty feet below the surface. The ice was a solid sheet seven feet thick and it was borne on a twelve-knot current. Into it the forest of piles was solidly frozen.
The spring breakup had begun on the river, the ice-cap, lifted twenty feet above its winter bed by the flood, was moving. The falsework, carrying a mass of unfinished steel, was fifteen inches out of line and had to be put back.
When the rising water began suddenly to lift the ice and with it the 450 feet of falsework on which the third span was being put together, there was a preliminary emergency of some consequence. It might easily be but an hour or two's work for the resistless river to wreck the
whole span that way. The emergency was met, as scores of others had been before.
The steam from every available engine was driven into small feed pipes and every man in camp was put to work to steam-melt or chop the seven feet of ice clear of the piles. And it was done. The holes were kept open through day and night of bitter cold and the hundreds of cross-pieces unbolted and shifted while the river rose twenty-one feet.
Then began the movement downstream. At first it was but an inch a day; then three or four inches. The melting and chopping went on almost unceasingly. Then the ice made its heaviest charge. A line was taken. The falsework was fifteen inches out and it had to be put back.
Anchorages were hastily built into the ice above the bridge and they were heavy anchorages. Block and tackle was rigged to them and while a gang thawed and chopped at the ice around the piles in the maddest of races the whole 450 feet of towering bridge was dragged inch by inch back into place.
You see, it had to be put back.
The rest was a still more furious race with the ice, for it was moving each day more freely. The last bolt of the span was sent home at midnight after an eighteen-hour day of one shift. The
Copyright. 1912. by Technical World Compaoy
THIS IS THE MILES GLACIER BRIDGE ACROSS THE COPPER RIVER. IN THE BUILDING OF WHICH THERE WAS A TERRIFIC RACE AGAINST THE SPRING BREAKUP OF THE ICE. The upper photo shows the men who won the bijr race with ice. and established a record in bridge building
be built across the river where it makes a double turn between the great living glaciers, Miles and Childs. Both present three-hundred-foot cliff-like faces to the water for three miles and if it were not for the turn between them the Copper Valley would be, as was once supposed, utterly impassable. Where the bridge must stand the current brings down an endless flotilla of giant bergs, many as big as a mansion, and would hurl them at twelve miles an hour against the bridge piers. In addition these piers must withstand the breakup of the seven-foot ice sheet under enormous pressure each spring. No such problem in bridge-building had ever been met before. It was one of the many "impossibilities" that faced Hawkins. A million dollars must be risked on the chance that he and his cohorts could build piers that the ice couldn't smash. And if they failed in this the whole $15,000,000 enterprise failed, for the Glacier Bridge was the key to the road and it was built under a battery of gloomy predictions as well as under a battery of bergs.
The great concrete piers, begun through the winter's ice, were driven forty to fifty feet through the river bottom to bedrock and there anchored. They - were built of solid concrete heavily reinforced with steel. A row of eightypound rails was set a foot apart all around and the whole structure bound together within the concrete in an amazingly massive manner. Then, above the piers, ice-breakers of the same construction were raised.
Before the pieces were half finished a lake burst out from the upper glacier and the river rose twenty feet in an hour. Here was a ticklish test—and the bridge stood.
On account of the floating ice no temporary bridge was possible here and work beyond could not wait two years for the big bridge. So a ferry was established in the stiller water above the bridge and almost under the shadow of the discharging glacier. Back and forth, all summer long, the ferry, built on the ground, of wood brought from "outside," dodged in and out among the bergs. Time after
s time the heavy piling of her temporary clocks was snapped out by floating ice. Almost infinite were the difficulties encountered but somehow, pile-drivers
O'Neal, would have thrown up his hands in hopeless despair.
Within an hour of the time the last piece was checked the first big girder was
in place. Ten and one-half days later the first span, 400 feet long, was completed. Nearly forty feet of towering steel structures a clay with a single shift of men, day after day, through the storms and the darkness!
But the second and third spans went faster still. The second of 300 feet, was built in six days and the giant third, of 450 feet, in spite of extraordinary difficulties, in an even ten days.
Map Of Alaska Showing The Region Tapped By
The Copper River Railroad. The Copper River country is rich in copper and coal.
and engines, horses and supplies, were got across and the line started on northward through the ensuing canyons.
Meanwhile the great piers were finished and in the autumn of 1909 the steel began to move forward from the East. It was not until late in the spring of 1910 that the last numbered piece was on the ground, the whole thing checked and rechecked in fear of a single miss, which might delay the whole great work a twelvemonth. This steelwork must be done in winter since no falsework would stand against the moving ice.
The checking of the steel was completed on April 5, which left less than six weeks to put together more than 1,100 feet of extra heavy bridge with a single crew of steel workers. Facing such a task and with the prospect of raging storms of rain, sleet and snow about half the time, almost anyone but Hawkins and his bridge engineer, A. C.