I told the boys they had so many interesting things going on at the mill that we should have to have a telephone between it and the cottage so that we could talk them over. XVII THE TELEPHONE The telephone was the great invention of our centennial year, 1876. Elisha Gray and Alexander Graham Bell each claimed to have been the inventor. It is quite probable that each did discover it independently, but the result of the long patent suit was that the court awarded the claim to Bell. It is, therefore, known as the Bell telephone. Many who installed telephones during the first few years of their existence had them taken out again as nuisances. They are far greater nuisances now than at that time, but the necessity of them has come upon us and entirely enslaved us. There were more than eleven billion messages sent by telephone in the United States in 1907. The capital invested in telephone business was $814,616,004. The income for that year was $184,461,747. All of these items had more than doubled during the previous five years. In 1880 there were about eight times as many miles of telegraph wires as of telephone wires. In 1907, there were about eight times as many miles of telephone wires as of telegraph wires. The Bell system had 3,132,063 stations, and independent companies had 2,986,515 stations in 1907. The first telephone line ran from Salem to Boston, Mass. This was in 1877. The next year the first telephone exchange was established. It was eight years before a telephone line was extended from Boston to New York. On October 18, 1892, the first telephone message was sent from New York to Chicago. Previous to 1895 telephoning, like telegraphing, was done by one wire, using the earth, as we say, to complete the circuit. But at about that time electric car and electric lighting lines became so common that they interfered with telephoning. These currents running in lines parallel to the telephone wires induced currents in them, and when a person put a receiver to his ear for conversation he heard the hum of electric light dynamos and the buzz of electric cars so loud that conversation was quite impossible. The next step was to introduce a return wire--the double metallic circuit as we call it. Thus outside currents induce equal and opposite currents in the two wires of the circuit, which neutralize each other. It was this same year, 1895, that the "central battery" system was introduced into telephone equipment. This is not usually a battery at all, but a dynamo. The price of all electrical supplies in 1895 was about one tenth what it had been in 1885, and at the same time the goods were of far better quality. Important telephone patents expired in this year, and immediately private and independent lines began to be established. It was also in 1895 that the telephone company began to use an automatic registering device which enabled it to charge telephone rates according to the number of calls.