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engine being open in its normal condi- relay coils reaches the proper amount tion. A short circuit is made between to attract the armature, and the local cirthe running rail and the live third rail cuit is closed, giving the audible or visif a switch is open; and in case a locomo- ible signal in the engine cab, or applying tive passes onto this section of track, the the brakes, according to the arrangebattery-relay circuit is closed by the run- ment thought best under the conditions. ning rails and the third rail which are This new system of engine cab signalthus electrically connected by the open ing has been installed on several miles switch. The signal will not be given at of the German State Railway system, and once, as the armature of the relay of the is said to be operating successfully. safety apparatus in the locomotive cab The system, moreover, includes prowill not be attracted until the distance vision for the locomotive engineer on from the signal where the rails are connected is such that the intensity of the current is sufficient to close the local circuit. A resistance coil of several ohms is connected with the live rail at distances of between 300 and 400 feet. When the locomotive reaches a distance from the open switch such that the resistance of these coils together with the rails has fallen to a predetermined value, the cur
TRACK WITH COLLECTOR RAIL INSTALLED ON ELEVATED RAILWAY STRUCTURE rent passing through the
order that there may be no failure of the automatic signaling due to the apparatus on the two trains opposing each other as a result of the batteries being connected in series or in opposition, thus causing the relays in one case to fail to work, a commutator has been provided on the axles of the trains so that the current is reversed periodically; and therefore the batteries will be in series or opposition alternately as the speed of the two trains is never likely to be the same. When a train stops, the battery is disconnected, and a connection is made from the center rail through the relays with the axle. These connections are the same as though the open switch closed the circuit, and any train approaching a stand
ing train would automatically give the GERMAN LOCOMOTIVE AND Coxtact RAIL FOR PROTECTION
alarm in both cabs. The system is said to be thoroughly practicable, and the
possibility of one engineer communione train communicating by telephone cating with another is certainly most with the engineer on another train. In
In unique and desirable.
OF TRAINS BY ENGINE CAB SIGNALS.
By E. S. Bisbee
ASHINGTON, D. C., has In its flight, the boomerang seems to organized the first boom- defy all known laws of projectiles; and erang club in the United in the hands of an expert, beautiful evoStates, perhaps in the lutions may be obtained from it. No one world. A short time ago a but the thrower ever knows where a
few gentlemen connected boomerang, after leaving the hand, will with the Department of Agriculture fall, but he can calculate to a nicety, the formed an association for the study and Australians manipulating them so well use of this peculiar weapon. They se- that they frequently catch them on their cured a large tract of open land in the return after a fight that would seem innorthwestern section of the city, and credible if it were not witnessed. The since that time have been busy with their boomerang will perform feats that are novel sport. They are rapidly becoming little short of miraculous; and, although expert in the use of this remarkable science has as yet failed to explain thorweapon, and there is no reason why the oughly the reasons for these peculiarsport should not be adopted in other sec- ities, it is understood that they are the tions of the country.
result of a combination of the form of The history of the boomerang is in- the weapon and the resistance of the air. teresting. It has been known to civilized This primitive weapon is made of a man for not more than a century, and is piece of wood about twenty-six inches in the weapon of the aboriginal Australian length by two-and-one-half in width, and bushman. Every traveler returning from one-third of an inch in its greatest thickthe island continent formerly had some- ness. The wood is steamed and bent thing to say regarding it, and a few to an angle of about 140 degrees, the inspecimens were brought back. But no ner edge being almost knife-like in its one ever has succeeded in mastering this sharpness, the outer more rounded. The weapon as it is mastered by the Aus- finished article looks not unlike an orditralians, though some wonderful feats nary sickle, and is thrown by grasping are performed with it in the hands of one end with the hand, holding the conexperienced persons. It seems to have vex side furthest from the body and probeen used for war purposes as well as jecting it straight away on a horizontal in the chase, and a blow from one will plane. Ash has been found to be the readily put an enemy hors de combat. wood best adapted to the making of
For many years it was generally be- boomerangs, because of its toughness lieved that the stories of travelers re- and correct specific gravity. garding the performances of this re- Any boy having access to a carpenter's markable weapon were made of whole shop and possessing a knowledge of a cloth assisted by a vivid imagination, but few simple tools, can make his boomerecently acquired knowledge has shown rangs; in fact, they can be made with that they will do all that has been claimed nothing but the wood, a spoke-shave, and for them. Considerable areas of terri- a piece of sandpaper ; but the original tory are necessary for the proper man- piece of wood should be secured from ipulation of the boomerang and great a turning mill because of the better facare should be taken by the neophyte un- cilities at those places for steaming and til their peculiar flights are understood. bending it to the correct shape for the They are far from being toys, but are ex- final touches. tremely dangerous weapons in the hands Let the wood be 3 inches in width, of inexperienced throwers, the novice one-half inch in thickness, and 26 inches never knowing where they will alight. in length, having an angle of from 120
to 140 degrees. The crude weapon, be- ball, always remembering to hold the fore steaming, must be twisted from left convex side outward and the tip perto right so that the outer edge of each pendicularly with the handle. Aim dihalf will barely project beyond the in- rectly at the tree and see what happens. ner edges. With this as a foundation, If the boomerang has been made corthe amatuer carpenter must shave the rectly, it will go toward the tree with wood so that the inner edge will be quite the speed of a bullet, but, before reachsharp and the outer but little less so, the ing it, will sail to the left, rise in the air,
and execute a beautiful circle to the right, returning to within a few feet of the thrower. This is the action of the righthand boomerang ; but they are also made for left-hand flights, in which
the twist must be made to the left instead of to the right. By varying the degrees of the angle and the weight of the weapon as well as the twist, many variations of flight may be secured.
For long-distance throwing, they should be made quite large, as the increased weight can te obtained only in this manner, and weight is what carries them through the air. The straight-away throwing with the weapon first described always results in one circle from left to right, but this may be varied by alterations in the method of throwing as well as in the force with which they are propelled through the air.
will result in perfecsides bulging so that the greatest thick- tion, and new throwers almost always ness is not quite half an inch. On the attain results differing from those of othend which is intended to be grasped by ers. An expert Australian thrower will the hand in throwing, there may be made spin one from him with seeming ease. It a few ridges so as to permit of a firm will strike the ground a short distance hold. Take this weapon into a large field away, bound into the air and skim along a and see what may be done with it. If few feet above the earth, then descend there are trees, so much the better for and again rebound over a tree, describe the beauty of the evolutions. Take a stand two circles and return to the hand of the fifty yards from a tree, and throw the thrower. Seeing is believing, and the boomerang as hard as you can at the writer has been a witness of feats more trunk and exactly as you would a base- remarkable than this during visits to expositions where exhibitions were given by ment of many effects from a single stick, native bushmen of Australia.
and the delights of studying the strange In all cases the boomerangs revolve on weapon are continual. One of the Austheir own axis, making a whirring noise tralians at the Omaha Exposition some and striking with great force. It is years ago, threw his boomerang to a disuseless to attempt to dodge one, for tance of ninety yards before it began its when it seems to be coming directly at return flight, during which it rose to a one it will swerve and go off somewhere height of forty-seven yards and deelse, for no one but the thrower knows scribed five complete circles, coming back what one will do when it leaves the and falling within two feet of the hand. Practice will result in the attain- thrower.
R. Wilkins had a dollar, so he said he guessed he'd pay
A little sum he'd borrowed from a gentleman named Gray;
I'd better pay that little debt I owe to McAfee;"
For when a dollar's started
On its debt-destroying way,
To the sums that it will pay.
Mr. Wilkins knew a kindness that he might have done for Gray
For a dollar or a kindness,
Rule is still the same, I say ;
Better start it on its way.