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Automatic Signal Lead MR. SJOSTRAND, a Swedish engineer, has invented an ingenious automatic signaling lead which affords a means of protecting a vessel from get ting aground when nearing the coast or whilst in dangerous waters. This is achieved by means of a "water-kite" fixed to a slender but substantial line in such a way as to remain always at a given depth with a given length of line, independently of the speed of the vessel. By paying out a sufficient length of line, the kite may be made to touch at any depth. As soon as the water shoals to the depth at which the kite is set, the latter, touching the bottom, causes a signal to be given in an apparatus installed on deck.

As seen from Fig. 1, the kite is designed like a roof with its planes aslant against the motion of the vessel, so as to cut down into the water when the latter is moving. It thus sinks to the bottom in the same way that an air-kite rises in the air. The wire to which the kite is fastened is kept strained, taking the shape of a bow. The bend of the curve is quite independent of the speed of the vessel, as the resistance of the water increases or decreases in the same proportion on each part of the line and kite irrespective of any alteration in speed. The actual ver

FIG. 1. SIGNALING LEAD CARRIED AT END OF CABLE.

tical depth at which the kite follows the ship, accordingly, depends only on the length of line which is paid out, being independent of the speed; this depth is read off the apparatus placed on deck.

As soon as the kite touches bottom

(Fig. 2), it is automatically detached from its couplings; and, the strain on the wire being removed, an efficient signal is given by the clockwork included in the its couplings, the kite rises to the surface apparatus on deck. Being now free from of the water, and, after having been hauled in, is ready again to be thrown

FIG. 2. WHEN THE LEAD STRIKES BOTTOM, A DEVICE IS UNLOCKED, RELIEVING STRAIN ON CABLE, AND WORKING SIGNALING APPARATUS ON Vessel.

into the water, after a slight adjustment has been made.

In dangerous or unknown water, or in foggy or misty weather, when approaching a coast, or in other difficult cases, the signal-lead will afford a certain knowledge of the minimum depth of the water throughout the ship's course. In fact when giving out as much of the line as corresponds to a certain depth of water, the lead will give a signal immediately the vessel gets into shallower water. The depth may be ascertained at any time by slowly giving out the line until the lead strikes bottom. And, finally, the lead may be used in connection with observations to be used for pricking charts, and will prove useful in saving time and work, the signal being obtained as soon as a certain depth is passed, without any slacking of speed.

The arrangement for signaling is a mechanism placed in a kind of cupboard on deck, which acts as soon as the strain on the line is released by the uncoupling of the kite.

Flying Machine Model Now [OW that the Wright brothers have made a successful flying machine it is natural that this new departure should attract the attention of a great many unscientific people who are interested enough to try a few experiments of their own. Not all, however, care to hurry life insurance along by testing mancarrying machines. Here is another line of endeavor for such.

Everybody has seen a bird soar and a few observers have spent a good deal of time and energy wondering how it is done. If they never tried to imitate they are probably still wondering, for mere watching the birds will never teach us to fly. A machine that will imitate the birds and give to a beginner his first lessons in flying is easily made out of inexpensive materials as shown in the sketch.

It is made of heavy drawing paper cut into the shape shown and braced with a thin piece of wood glued on top. The weight which is glued to the bottom of the model and which corresponds to the body of a bird may be made of any piece. of wood or rubber shaped so as to present the least possible resisting surface to the action of the wind. The wings are curved as shown in the end view and the tail should be bent slightly upwards. The position of the tail, the curvature of the wings and the location of the weight will have to be altered in winds of different speeds in order to make the model fly at its best.

To test one of these gliders it is best to begin by casting the model from the hand at a height of about six feet and by comparing the action of the glider in each flight ascertain the correct adjustment of the wings, tail and weight. It may then be launched into the wind from any height with the assurance that the resulting flights will well repay you for the time spent in making and testing it. Much can be learned by watching the flights of this and similar models, and it is not long before the experimenter learns just what changes in the machine. are necessary to produce certain results. To the beginner, however, the accompanying table of cause and effect may come in handy in clearing up some of his principal difficulties.

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Cycles for Police and Soldiers

D

By Fritz Morris

EVELOPMENT of the bicycle-police idea has been steadily growing in many of the big cities of the world and American cities have not been behindhand in making use of the wheel as a help to their police departments. But the city of Brussels has an organization, perfected within the past five years, which, in some features at least, leads other municipalities along this line, and which in some respects is unique.

The bicycle police of Brussels ride chainless wheels, carry neither swords nor clubs and are armed only with re

volvers, which they are not supposed to use except in extreme emergency, yet their service is competent and effective. They ride the boulevards and greater thoroughfares always in pairs, and traffic of all kinds is absolutely under their control. Motorists and cyclists have a wholesome respect for them, for they carry speed indicators on their wheels and when an offender against speed-limit regulations appears, they have only to follow him a short distance to secure certain proof of his offense. Arrest, immediate or subsequent, is sure to follow and fitting penalty is exacted. The men are carefully selected for their task upon the streets, are experts in handling blockades and other street troubles and are under a system of telephone reports and Icalls which makes them quickly available at any point. The statement is made by observers of their work that two mounted men are worth ten foot-men. They are also used as messengers in all sorts of police duty.

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BELGIAN SHARPSHOOTING RIFLEMEN WITH THEIR FOLDING CYCLES.

During the last ten years the Belgian army has made use of the bi

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BELGIAN RIFLEMEN, FIRING, WITH THEIR FOLDED CYCLES ON THEIR BACKS.

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A SQUAD OF BRUSSELS POLICEMEN WITH CYCLES, HOLDING A CROWD WAITING FOR THE
START OF A CYCLE RACE AROUND BELGIUM.

cycle, also, for mounting a force of riflemen. They use a folding wheel and are armed with the regulation service rifle. Being picked men, and crack shots, they give excellent service as scouts, for they can cross all sorts of country, riding when possible and carrying their folded wheels when not. In their sober, dark green uniforms, with yellow trimming and cloth caps they are neat but not gaudy and are a very useful body to the service.

Sham battles are very popular with the Belgians. When one occurs the people turn out en masse to witness the spectacle. Shops are closed and the citizens arrayed in their best garments, the ladies in gaily colored finery, add interest to the maneuvers. Belgium is one of the minor military powers of Europe that dread the aggressions of their of their more powerful neighbors, notably Germany. Hence she represents the latest innovations in all things pertaining to military science and tactics.

The bicycles used as a regular part of their equipment by the sharp-shooters hitherto referred to are necessarily of the very lightest build and weight, compatible with strength and service; for a few pounds extra weight on a soldier's

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Seeing Through a Brick

By Livingston Wright

ANA DUDLEY of Wake field, a suburban town of Boston, has devised the application of the "seeingthrough-a-brick" principle to a machine which will enable you while seated in your luxurious office chair or your comfortable, lazy library chair, to turn to a sort of "receiver" and take a squint at what your employees are doing 'way up at the southeast corner of the 'steenth floor above you, or turn from the pages of your ev

THE INVENTOR AT HIS INSTRUMENT.

ening paper or magazine to a comfortable parental peep at your dear little tots in the nursery above. Indeed, if you should feel disposed to peer over into the next county or the next state you can look at your business friend the while you talk with him over the 'phone. Dudley's brain has hatched the basic contrivance that will enable you to do these very things and many others as wonderful.

It may be that Dudley will never realize his deserved fortune from his present "seeing-through-a-brick" device, but

there is little question that his invention will be added to and perfected by others, so that vast manufactories will find it as indispensable as the telephone, houses will have it as much a matter of equipment as open plumbing, great office buildings will be using it to communicate with other great office buildings hundreds of miles away.

For, there are times and callings when for a man to gaze upon the distant face of another may be just as consequential as to hear that person's voice. Think of what it would mean for a manufacturer to have the power of quietly and unsuspectedly watching his employees while they are at work. Think of what it would mean for the bank official to be able at any moment he might choose, to peer into the bank vault just before he

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