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Great Drawbridge Towed to
VOR the completion of the west barges on the water end, and then pulled
branch of New York's great sub- into position and anchored. This was way, which is now running from done without disturbing traffic.
the Battery to the Harlem ship Both draws are 272 feet long, the old canal (commonly known as the Harlem one weighing 1,200 tons and containing river) at Kingsbridge—a distance of a steam operating outfit in the turret. fourteen and one-quarter miles—it was four barges, having a combined capacfound necessary to replace the old draw- ity of 2,500 tons, were securely lashed in bridge at this point with a double- pairs, and loaded to the required height decked structure specially designed to ac- with suitable heavy blocking, as seen uncommodate the subway train traffic, der the draw in the photo. These were which near this point emerges from the then drawn into place at low tide, two tunnel and continues as elevated to the on each side of the center bulkhead; terminal.
partly submerged; and finally blocked The stupendous proposition—which close under the bridge. Then, with the was effectually carried out—was to lift rising tide, and emptying the barges simthis draw from between its approaches, ultaneously with a pair of powerful cen
NEW DRAWBRIDGE TO REPLACE OLD STRUCTURE OVER HARLEM RIVER.
Showing manner in which it was built on piles.
tow it one and one-quarter miles, and trifugal pumps, the draw was easily place it in a new position, repeating this raised almost two feet above the apoperation in replacing it with the new proach level. structure. The old approaches, 100 and Now the journey began. With two 112 feet long respectively, were first re- tugs pulling, and two in the rear to conmoved and replaced with the new ap- trol this unwieldy mass, it was successproaches of the same length, weighing fully navigated around a difficult curve 300 and 400 tons. These were built close and deposited over its new position, in to and parallel to the old approaches, on less than twenty-five minutes. The barges railroad trucks on the shore end and were then again gradually submerged un
til the structure was accurately centered, when they were withdrawn to be used again.
One of the accompa nying photographs shows the draw on its way. The end of the bulkhead from which it was taken is seen on the extreme right over the water.
The other photograph shows the new doubledecked draw whose superstructure supports three tracks. The king post is 98 feet above
OLD DRAWBRIDGE OVER HARLEM River BEING REMOVED TO New Site, mean water-level; it
Rests on timber falsework carried by barges towed by tug. weighs 2,000 tons and is operated by electricity. As shown, it was weight, the clearance between the bulkbuilt on piles in a position where it head center and bridge guide wheels was would not interfere with canal traffic, only four inches, necessitating quick, acabout seven-eighths of a mile from its curate work in lowering the bridge (by future position. The spaces at each end submerging barges) before the tide and were left open so as to enable the en- current changed. gineers to place the barges. This struc- Although the Rapid Transit Commisture also was successfully moved at high sion, who undertook the work, had obtide, June 16, the whole operation being tained a permit from the United States done in about twenty-five minutes from Government to close the canal for three the time it left the piles until it was over days, it was actually closed only during its new position.
the time that the structures were being On account of the 800 tons more moved.
Steam Color Scintil.
lator HIS latest electrical invention is the
work of W. D'Arcy Ryan, illuminating engineer of the General Electric Company, and bids fair to supersede the electric fountain that has so long held preëminence as a spectacular feature. The Scintillator has recently been tested nightly at Nahant, Mass., before shipping to Jamestown, Va., where it is to be used as an important illuminating feature
projected in any combination desired on a curtain of steam issuing at high pressure from an arrangement of pipes and nozzles. These nozzles can be arranged for a great variety of effects. A long, horizontal pipe, with nozzles at short intervals arranged to throw the steam vertically, forms a curtain on which the beams of light are thrown. Each searchlight is equipped with transparent screens of five or more colors. The effect of these lights, when thrown on the steam, is startling and beautiful. A number of figures can be worked out by suitable manipulation of the lights. The projectors are arranged to be thrown out of focus, if desired, so as to obtain either a very concentrated beam or rings of light of varying diameters. In this way it is possible to project on the steam curtain a number of colored rings around a common center. By varying the color screens, kaleidoscopic effects are obtained.
The possible combinations are limited only by the ingenuity of the operator. Fans, pinwheels, sunbursts, star effects, waterfalls, etc., can be mounted on a single inconspicuous fixture. For instance, most amusing effects are obtained by causing steam to issue from a number of loose pieces of rubber hose, and throwing the light on the wriggling steam jets, suggesting the motion of a huge serpent.
Bombs are shot into the air, containing a mixture which, when exploded, forms clouds of dense smoke; or the bombs may contain confetti. When these clouds of smoke or confetti, as they float away, are followed by the light, the effect is very pleasing.-L. I. HARRIS.
SCIENT FIC AMERI.AN,"
Winged Aëro Machine
W feet from tip to tip, M. Florencie, member of the Aëro Club of Paris, seeks to solve the secret of successful aërial navigation. The "orthopter” or “fappingwing” machine, as it is called, consists of two aëroplanes partly covered with canvas, the remaining portion of each being designed so as to imitate the action of a bird's feathers in flight. The machine, which weighs but thirty pounds, is fitted to the aëronaut's body. His legs furnish the propelling force. He stands in stirrups, and by means of a cord from foot to wing, flaps the great Africa. The boat is specially built for pinions. The wings are lowered by out- service in shallow waters. In order to stretching the legs; a spring fixed to the secure this end, it was necessary to conframe raises them. A series of longitud- struct it on somewhat awkward lines. inal flaps make up the "feathers” of the Nevertheless, owing to its powerful enmachine. A rudder in the rear acts as gines, fair speed can be attained. On its the tail.
trial trip, bearing a load of four tons, and with a draught of 12 inches, it made eight
knots an hour. The boat is constructed Light-Draught Launch
of galvanized stecl. In length, it is 56
feet 3 inches: beam. 9 feet. The hull is THE accompanying illustration is from subdivided by six water-tight bulkheads,
a photograph of the motor-launch a deck being formed by fitting floor Spider, recently constructed for British boards along the bottom of the boat. In government service in southern Nigeria, order to facilitate steering on the light draught, three balanced rudders are pro- the jungle, it will go hard with him. vided.
When alone, the bird will not attack.
often numbering several thousand, the Wood Conquers Stone bird will seek out his hereditary foe and OT even rocks can withstand the
give battle. On such occasions the tiger gentle but persistent and resistless
seeks safety in flight.. A hand thrust into force put forth by Nature in her proces
a cage filled with these little gamesters ses of plant growth. A remarkable in
will elicit a furious assault from their combined forces. Assembled en masse, they know no fear.
Horse Digs a Well OUT on the Arizona desert they use
horses for some odd purposes. In this case the horse has actually been put to work digging a well in the hope of finding water. The mode of digging is as follows: The horse is driven into an enclosure, the bottom of which is an endless chain consisting of slabs of wood revolving around iron cylinders placed at each end. In the effort to walk, the horse, of course, turns this treadmill. One of the cylinders is attached to a shaft, which, as it moves back and forth, pulls up and down the walking-beam shown in front of the treadmill. Passing through the right-hand arm of the walking-beam, is a rope to which is attached the drill. When the shaft fastened to the treadmill! is pulled backward, the drill is raised; and when it moves forward, the drill is lowered. In this way the apparatus is forced into the ground on the same principle that a pile-driver forces down piles in building wharves and other structures.
stance in evidence of this may be seen near the city of Waterbury, Conn., where a large, sturdy oak tree has performed the unusual feat of bursting its way through a thick stratum of rock. As shown in the illustration, the tree appears to be growing directly on top of the stone; in fact, the pressure exerted by it when growing was sufficient to rend the rock apart. The displacement of the rent rock is quite apparent in the picture.
Tiger's Tiny Foe THE tiger bird, so-called because he is I the one thing the royal beast of India fears, is no larger than the English sparrow. Yet so bold and combative is he, that if the great cat is surprised by a sufficient number of the little creature's kind far from the protecting shelter of