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At the end of 1909, there were no fewer than thirty-six wireless telegraph companies with the preposterous capitalization of $132,560,000. The greater part of this vast issue of stock, much of which is worth no more than the prevailing rate for waste paper, has been exchanged for the hard earned savings So successful were of small investors.

the operations of promoters of this kind of stocks that the postoffice department was obliged to interfere. One raid last November was upon the offices of a wireless combination capitalized at $14,000,000. The assets of the concern were so trifling that the stock of one constituent company was turned into the treasury at 20 cents a share. Yet this same stock was unloaded on the gullible at $10 a share. Within a radius of five hundred miles of Cincinnati half a million dollars had been invested in this kind of stock before the raid.

In this particular the wireless telegraph is but repeating the history of the

railroad. About seventy years ago, after the railroad had given some indications of its capacity for future usefulness, England went stark, staring mad over speculation in railroad shares. Hundreds of wildly impracticable schemes together with quite as many downright frauds, were floated as fast as the printing presses could turn out the stocks. It seemed as if the savings of the entire nation were poured into these schemes. Certainly a great many million dollars were thus thrown away. Then the bubble burst and the ruined dupes went to work again to earn more money for the next plausible swindler that came along.

It is not likely that the operations of the dishonest will do any more real harm to the wireless telegraph than they did But at least the exto the railroad. posures of last summer should serve as a warning to all who long for sudden wealth to exercise self-denial in the purchase of temptingly offered wireless. telegraph stock.

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REBUILDING QUEBEC'S

C

FALLEN BRIDGE

By

CHESTER CARTON

ANADA is bent upon having the world's biggest bridge, no matter if it does come high. The Quebec bridge across the St. Lawrence, which collapsed when half completed, on August 28, 1907, carrying seventy-four of the eighty-six men on it down to death, cost the Dominion $7,154,987. Just as soon as the weary round of official investigations had been finished an international board of engineers was assembled and told to try to design a bridge that could stand alone, to be erected on the site of the failure. This board, consisting of H. Vautelet, of Montreal, Ralph Modjeski, of Chicago,

and M. Fitzmaurice, of London, with Alfred Noble, of New York, and H. Holgate, of Montreal, as consulting engineers to help untangle the knotty problems, advanced far enough with their plans to allow preliminary work to be commenced a year ago on a structure which, when completed, is expected to cost somewhere near eleven million dollars, thus bringing the total outlay for a means of getting the trains of the new transcontinental railroad across the St. Lawrence, up to eighteen million dollars.

Still, it will be worth the money; for the Canadians will be able to boast the possession of a bridge the main span of which will be 48 feet longer than the

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NINE THOUSAND TONS OF STEEL, BENT AND TWISTED INTO INDESCRIBABLE CONFUSION,

WHICH HAD TO BE CLEARED AWAY.

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THE QUEBEC BRIDGE AS IT LOOKED A MONTH BEFORE IT FELL. The new bridge will be quite similar in appearance.

cantilever spans of the famous Firth of Forth bridge, and 162 feet longer than the Brooklyn bridge. Let them make the most of it, for when New York gets around to bridging the Hudson the Quebec affair will look like a mere culvert by comparison. Indeed, New York City already has bridges that cost a great deal more than the Quebec structure, thanks to the highly developed Tammany art of making three dollars do the work of one. In mere height above the water, too, the Quebec bilge is far excelled by a number of bridges scattered over the world. One of these is the St. Giustina bridge in the Tyrol, which is 460 feet above the water; that is, from the surface of the water to the top of the rail, as compared with a beggarly 150 feet at Quebec. The Fades bridge in France is 435 feet above the water, the Garabit bridge in France 406 feet, the Zambesi bridge in South Africa. 420 feet, not to mention a number of others that are more than three hundred feet high. Mere height above the water and cost, or rather expenditure, however, do not count in bridges; it is the length of the span that confers distinction.

The new Quebec bridge is to be only 3,232 feet long over all as compared with a total length of 8,296 feet of the Firth of Forth bridge; but its central cantilever

Scotch

span is to be 1,758 feet long as compared with 1,710 feet, the length of each of the two cantilever spans of the bridge. Lest the Canadians should become unduly puffed up over this prodigious span they should remember that that is nothing at all to what the engineers could do if they wanted to, according to their own story. A commission of army engineers appointed by the Secretary of War in 1894 to investigate the practicability of bridging the Hudson at New York City with a span of 3,100 feet, reported that under certain conditions the practicable limit of length in a bridge span was 4,335 feet. Not to be outdone, Gustav Lindenthal, an American engineer who had not been consulted about it, in commenting upon this report declared in a magazine article, under his own signature, his firm conviction that a bridge with a span of 6,000 feet long could be built on which trains could run with safety at express speed. So far no one has ventured to outtalk Mr. Lindenthal on bridge building.

However, the Quebec structure will be a very fair sort of bridge, considering. The tops of the main posts will be 448 feet above the water as compared with 361 feet in the Forth bridge. The latter only carries two railroad tracks, while the Quebec bridge will have two railroad tracks, two street railway tracks,

SIDE VIEW OF THE BRIDGE THAT FELL, TAKEN FROM CHAUDIERE BRIDGE, ONE MILE DISTANT.

two horse and motor roadways and, finally, two sidewalks.

The new Quebec bridge is proportioned for a load twice as great as the one which collapsed was designed to carry, while its bottom chords will have five times the strength of those in the old one. Designed for a load 2.98 times that of the Forth bridge, or 13,340 pounds per lineal foot as compared to 4,480 pounds, it will weigh 2.3 times as much per lineal foot. The heaviest bottom chord will weigh 160 tons, the pedestals, upon which the main posts will rest will be 19 feet high and weigh

500 tons each, while the posts themselves will weigh 900 tons each. The total weight of the bridge according to the official plans, will be 145,000,000 pounds as compared with the Forth bridge's weight of 114,000,000 pounds.

One of the difficulties confronting the board of engineers was that the actual strength of steel members of great size is unknown. Such definite knowledge of steel as is available has been obtained by testing small pieces. Calculations for larger sections were based on these known facts. But evidently there is a big difference between the theoretical

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THE PIER, AND A PORTION OF THE BRIDGE ON THE NORTH SHORE-OPPOSITE. This was the bridge that fell.

and the actual strength of large members, for otherwise the original structure would not have collapsed.

In order to afford the engineers a more substantial basis of facts upon which to build their calculations Parliament appropriated $30,000 to pay for a series of tests of models of columns and girders. These models, some of which weighed as much as 6,850 pounds, were placed in a testing machine, having a capacity of 2,800,000 pounds, at Phoenixville, Pennsylvania, in which they were slowly crushed while a squad of engineers looked on, took measurements and made notes. Armed with the data thus obtained the Board of Engineers worked out its design with some assurance that it would stand the test of time. The official plans call for a cantilever structure; but the contractors who submit bids are invited to offer suggestions for any changes they think will be improvements. If they meet the approval of the engineers the changes in the official plans can be made, but the contractors must take all the risks. Prospective bidders

were warned that they must clearly understand that they must be prepared to undertake the entire responsibility, not only for the materials and construction, but also for the design, calculations, plans and specifications and for the sufficiency of the bridge for the loads specified.

It was a strange task which confronted the contractor who undertook to remove the wreckage of the collapsed bridge. Nine thousand tons of steel, bent and twisted into indescribable confusion, lay between the shore and deep water. There was no place to begin, for there were no loose ends. So well had the steel makers done their work that but a single eyebar was broken in the collapse. Starting in January, 1910, the contractor was allowed until May 1, 1911, a period of less than sixteen months, in which to clear away the wreckage, including all that showed in the river at low water.

Two months were spent in experimenting, trying to find a vulnerable spot in the wreck and some efficient method of cutting up the ponderous members of

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