Chapter 50
Section 50 of A Thousand Things Worth Knowing. This is a LibriVox recording. All LibriVox recordings are in the public domain. For more information, or to volunteer, please visit LibriVox.org. Recording by phone. A Thousand Things Worth Knowing by Nathaniel C. Fowler Jr.
Sunday Schools The Sunday Schools of the United States have a membership of about 15,500,000, including teachers. The Sunday School membership of England and Wales is over 7 million. Connected with the Sunday Schools of the world are about 2,650,000 teachers and 26,500,000 scholars. Talking Machines
The Talking Machine, known by several names, including the phonograph, was originally invented by Edison. Unscientifically speaking, it consists of a disc similar to that used in a telephone, with a needle or point attached to the centre of the underside of it. This needle or point fits into circular or cylindrical grooves, which are covered with tinfoil or other malleable substance. The vibrations of the point or of music, which reach the disc, cause this needle or point to rise or fall, producing impressions upon the tinfoil or other substance. After the record has been made, duplicates are produced in a substance largely made of rubber, which is placed on a rotary disc or cylinder that is turned automatically,
the needle or point attached to the disc working into the grooves and rising with or following the impressions, which cause the plate or disc to vibrate. This process is wholly mechanical and electricity is not used. Tariff This word, meaning a schedule of duties on merchandise, imported or exported, is said to come from Tarifa, a town in southern Spain on the Mediterranean Sea, where duties were once levied by the Moors and on all ships passing in or out of the Straits of Gibraltar.
Telegraph The conception of the telegraph came to Professor Moors in 1832, while he was making a voyage from Europe to America, and he at once began his experiments, which resulted in what may be considered one of the two greatest inventions or discoveries. After waiting about eight years, Congress reluctantly appropriated the sum sufficient to build a telegraph line between Washington and Baltimore. The original conception of telegraphy belongs wholly to Professor Moors, but since its invention, other scientists have invented improvements,
including an apparatus which allows the sending of two messages each way, or four messages in all, over the same wire at the same time. The telegraphic code or alphabet, originally invented by Moors, remains practically intact. It consists of dots and dashes, and may be learned in a few hours, although expertness requires a year or more of practice. Unscientifically speaking, the telegraphic apparatus is extremely simple. It consists primarily of a piece of soft iron around which is found several strands of insulated wire.
During the time that electricity is passing through this wire, the soft iron becomes a magnet, but returns to its non-magnetic character when electricity is not passing around it. A battery is used for the generating of electricity. The operator turns electricity into the wire by pressing a key. When the key is down, the electricity passes around the piece of soft iron and makes of it a magnet,
which will draw iron or steel to it, the same as does any ordinary permanent magnet. Just above the end of the soft iron is placed a piece of metal, and as the key is pressed, letting in the electricity, the iron, then a magnet, draws this metal to it, producing a slight sound or click. This piece of iron is held by a spring, and springs back into place when electricity is let out of the insulated wire surrounding the soft iron. If a message is to be sent a long distance, a relay is used so as to turn into the wire additional currents of electricity,
because electricity loses some of its strength if carried over a very long wire, and the relay adds new or fresh currents from separate batteries. In this way, a message can be sent continuously for several thousand miles, which would be impossible without the use of relays. The process of sending several messages at the same time over the same wire is somewhat complicated.
The result is obtained by using currents of electricity of different intensity, the currents not interfering with each other. The ocean cables are described under another heading. End of section 50, recording by phone.
