Vietnam or Thailand ? Vote for the TOP Country of the Week !


He was in youth apprenticed to a bookbinder, "and many of the books he bound he read." A line in his indentures says: "In consideration of his faithful service, no premium is to be given." Striking the leg of a horseshoe magnet with an iron bar wound with insulated wire causes a contact between loose end of wire and small disc, and a spark. Faraday's First Magneto-Electric Experiment.

We come now to another consequence of Oersted's great discovery, which is doubtless the most important of all, namely, the generation of electricity from magnetism, or, as it is usually called, magneto-electric induction.

This apparatus was completed on June 2, 1875, and the same day he succeeded in transmitting SOUNDS and audible signals by magneto-electric currents and without the aid of a battery.

The carbon, or microphone transmitter, was found superior to the magneto-electric transmitter of Bell; but the latter was preferable as a receiver to the louder but less convenient chemical receiver of Edison, and the most successful telephonic system of the day is a combination of the microphone, or new carbon transmitter, with the Bell receiver.

'I have rather, he writes in 1831, 'been desirous of discovering new facts and new relations dependent on magneto-electric induction, than of exalting the force of those already obtained; being assured that the latter would find their full development hereafter.

There must be motion to induce a current of electricity to flow in a wire circuit. Faraday's great discovery was, in fact, that when the pole of a magnet is moved into, or moved out of, a coil of wire, the motion produces, while it lasts, currents of electricity in the coil. Such currents are known as "induced currents;" and the action is called magneto-electric "induction."

The principle of this invention is the supplying of a magneto-electric current from a small magneto-electric machine attached to the card, speeder, or whatever machine it may be applied to which generates the current, and this machine is driven by a small belt from the main driving shaft.

If, however, the electric current, instead of being developed by chemical work in a battery, is produced by ordinary mechanical power in a magneto-electric or dynamo-electric machine, the case is different; and the double transformation, first of the mechanical force into an electric current, and then of that current into mechanical force, furnishes a means for effecting the conveyance of the power to a distance.

A few experiments soon showed that his reed had been set in vibration by the magneto-electric currents induced in the line by the mere motion of the distant reed in the neighbourhood of its magnet. This discovery led him to discard the battery current altogether and rely upon the magneto-induction currents of the reeds themselves.

"I have rather, however," he says, "been desirous of discovering new facts and new relations dependent on magneto-electric induction than of exalting the force of those already obtained, being assured that the latter would find their development hereafter." How profoundly prophetic!