Action at a Distance - Modern Wonders Wrought by Electricity

A Suggestion to Tesla - His System of Controlling Vessels - Power Transmission

The suggestion was made not long ago by Szczepanik, the Inventor of the telectroscope, that Mr. Tesla might find a flying machine a good subject for experiment, in testing his apparatus for controlling the movements of a vehicle at a distance. The idea is not a bad one; but it involves difficulties which the young Pole probably has not considered.

Mr. Tesla had in view, when he worked on his scheme last summer, the control of marine vessels capable of carrying a storage battery and propelled and steered electrically. But a storage battery is heavy, and, although it has been tried on a small scale in aerial navigation, the tendency of late years has been toward the construction and use of extremely light steam or gasolene engines instead of electric motors. In this manner it seems to be practicable to reduce the weight of the machinery in proportion to the power developed. In so dense a medium as sea water a craft laden with a considerable number of accumulator cells would easily preserve its buoyancy, but the case is different with an airship. Again, it is the ambition of the aerial navigator to traverse scores, even hundreds of miles, after once launching out upon a voyage, whereas Mr. Tesla, while studying how to project against an enemy’s warship a more formidable quantity of high explosives than has hitherto been used, apparently contemplated shorter trips.

In view of the lively interest now taken by the enlightened public in electrical action at a distance without wires a fresh consideration of Mr. Tesla’s plan is not out of place. In his patent, applied for last July, and taken out in November, he says:

The invention which I have described may prove useful in many ways. Vessels or vehicles of any suitable kind may be used, as life, dispatch or pilot boats or the like, or for carrying letters, packages, provisions, instruments, objects or materials of any description, for establishing communication with inaccessible regions and exploring conditions existing in the same, for killing or capturing whales or other animals of the sea, and for many other scientific engineering or commercial purposes. But the greatest value of my invention will result from its effect upon warfare and armaments; for, by reason of its certain and unlimited destructiveness, it will tend to bring about and maintain permanent peace among nations.

Mr. Tesla provides for a base of operations on the shore or on a big ship at sea. Here the man who controls the movements of the crewless torpedo-boat has before him a rotating device or switch, one complete turn of which admits four momentary impulses to a vertical wire and sends them off into the earth or other conducting medium. The wire leads down into the earth and upward along a pole, terminating overhead in a flat metal plate. Several forms of apparatus for generating the electric waves are mentioned as available for this service. They resemble in general the appliances which Mr. Tesla has proposed to use for wireless telegraphy.

The small boat is equipped with an uplifted metal plate, a wire running down from it into the vessel, a sensitive device through which any impulse excited in this “receiving circuit” must flow, and, finally, a wire leading to the keel of the boat and thus to the sea. As has been mentioned already, the boat carries a storage battery, and there are several wire circuits, each leading to a different set of instruments. These wires behave much like pipes on a steamship which conduct steam along various routes to perform different kinds of work. In each auxiliary circuit, acting like a valve to admit or shut of current, is the familiar “relay” of the telegrapher. This mechanism is so constructed that an exceedingly faint current, passing through one part of it, automatically opens up the way for the flow of another current through another channel.

But the master instrument is the sensitive device in the receiving circuit. This is so arranged that it already has a weak current trying to flow through it, and needing only the least imaginable additional stimulus to promote success. The needed impulse is derived from the vibrations emitted from the distant land station, and communicated through the ether, sea or earth. The sensitive device performs somewhat the same function as the “coherer” of a Marconi telegraphic system, but is an original affair in design. Mr. Tesla regards it as much more trustworthy and efficient.

It is not necessary to describe in detail the apparatus inside the boat. It suffices to say that it has been tried in a model and works to perfection. The distant operator, by his manner of moving the switch, can start the boat ahead, stop it, and steer it to the right or the left. Automobile torpedoes carry a charge of one hundred or two hundred pounds of guncotton. A boat like this of Mr. Tesla might bear tons of explosive and work the instantaneous ruin of the stoutest war vessel ever conceived. No wonder that he regards himself as the ally of the Czar of Russia in putting an end to war!

The plan of producing action at a distance should not be confounded with that other startling project which Mr. Tesla broached last summer - the transmission of power through the upper air. In the work just described, only a very small quantity of energy is employed, and it unlocks another store of energy already existing at the distant point. Moreover, the vibrations are transmitted, not by the air, but by the land, sea or what the scientist, not the poet, means when he uses the word, “ether.” But Mr. Tesla’s new power-transmission scheme contemplates such work as is now being done between Niagara and Buffalo, where several thousand horse-power in the form of electricity are sent over costly copper rods, mounted on a pole line and carefully insulated.

Not only is it proposed to convey enormous quantities of energy from one place to another over distances of hundreds of miles, but to dispense altogether with the metallic conductor and use the air instead. At ordinary densities, especially when dry, the air is an insulator, and not a conductor: But when sufficiently rarefied it will conduct admirably; and as the atmosphere grows more rare as the distance above the earth increases , one needs only to get up to a certain elevation to find the right degree of rarefaction.

The current which Mr. Tesla would use for this purpose would possess a very high potential or voltage , and this would be secured by a newly invented apparatus of his, a peculiar type of “transformer.” Every schoolboy knows nowadays that when a current is transformed upward, the voltage increases, but the quantity, as expressed in amperes, is reduced. The total amount of energy is unchanged. A current of 300 amperes, sent at 25,000 volts, is equivalent to 7,500,000 watts or 10.000 horse-power. But if this current were transformed into one of a single ampere and 7,500,000 volts, it would still be equal to 10,000 horse-power.

Now, Mr. Tesla has already experimented with a voltage of several millions, and he believes that he could transform up to 100,000,000 volts. If, at such a potential, he had one whole ampere , he would be handling 133,333 horse-power! He conceives it possible to transmit a current like this for hundreds, not to say thousands, of miles, with the air as a conductor in the same sense that copper wire is.

At the present time, however, he is not ready, to explain how he would support in the upper air the terminal apparatus of his sending and receiving station, nor to talk about plans for making a commercial application of this remarkable idea.