I thought this short piece would be appropriate for the DST to real time changeover weekend. I wonder if there are any "time balls" left in cities, save the one that falls on New Year's Eve in New York City?It has taken old Father Time a long while to get the world into good, regular running order as it is to-day. For many hundreds of years people had very strange and uncertain ways of telling time, for they did not have any clocks or watches to mark the hours. In fact, they did not even know anything about hours or minutes, but reckoned time merely by days and months and years, although they never could agree when the day began. Some said it began at sunrise and others thought it began when the sun set, while some said it did not begin until midnight and still others were sure it began at noon.
Well, after the world had gone on for a long while with its days, months, and years, the day and night were finally each divided into twelve parts, or hours. It mattered not how long or how short the daylight part was, it was divided into twelve hours just the same, for the hours were lengthened or shortened to suit the length of the day in the various seasons of the year. In some of the long summer days each hour had seventy-five minutes, while in the short winter days, when the hours had to be crowded so as to get them all in between sunrise and sunset, each hour had only forty-four minutes.
These hours were measured by sun-dials and hour-glasses and candles and other curious time-pieces, which were about as changeable and uncertain as the hours themselves. Of course when clocks were invented such things went out of use, for clocks were so much more accurate and reliable, and would keep on recording without having to be watched all the time to see that they did not stop or run out.
At first clocks were crude affairs, and were not much to be relied upon. They could not well be made for house use, and were chiefly placed in the towers of churches and town halls. Each morning and evening the clock bell would ring at a certain hour, so that all within sound of its deep note could keep track of the time, and, if they were fortunate enough to have a clock at home, could set it to agree with the town clock, which was more likely to be correct than their own. But now Uncle Sam does a similar service for the people all over this great country by sending at noon each day an electric signal which enables them to set and regulate their clocks and watches. The work is done by officers and clerks in the United States Naval Observatory at Washington, where they make careful calculations and look after the great clocks that regulate the time of the country. Some of the college observatories also furnish several portions of the country with standard time much in the same way as does the Naval Observatory. Readers of St. Nicholas will remember an interesting article printed a year ago, describing the taking of the time at Goodsell Observatory, and entitled "How We Set Our Watches by a Star."
Until a few years ago each town and city had its own time, for, as you know, time is reckoned by what are known as meridians of longitude—imaginary lines running north and south on the earth's surface. You all remember these lines running up and down across the maps in your geographies. Now when the sun is directly over one of these lines it is noon at all places that happen to be on that meridian, but of course places lying east and west of this would each have a different meridian and therefore a different time.
This was good enough before the days of the railroad and the telegraph, but now it would be a tremendous bother if each place were to use its own local time, and so we make use of a system called standard or railway time.
According to this plan the country is divided in such a way that there are only four different times in the entire United States, each exactly an hour different from that of the adjoining divisions. Thus when it is twelve o'clock at New York it is eleven o'clock at Chicago, ten o'clock at Denver, and nine o'clock at San Francisco. These different standards are called Eastern Time, Central Time, Mountain Time, and Pacific Time, and the time of all places in any one of these divisions is precisely the same, no matter what their local time may be.
In Europe some of the countries calculate their time from the meridian that passes through Greenwich in England, but the United States calculates from the meridian that is seventy-five degrees west of Greenwich. When the sun is directly over this meridian, it is said to be noon at Washington, Philadelphia, New York, Boston, and all other towns and cities in the Eastern division.
Strange as it may seem, Uncle Sam does not make use of the sun for reckoning time, but, as already described in St. Nicholas, he turns his attention to some of the regular steady-going stars, or "fixed stars," as they are called. Every clear night an astronomer with a big telescope looks at certain of these stars and makes his calculations, from which he can tell just when the sun would cross the seventy-fifth meridian. One of the great clocks in the observatory is called the transmitter, because it transmits or sends out the signal that keeps standard time. This clock is set and regulated by the star-time, and then every day at three minutes and fifteen seconds before twelve a switch is turned on and the beats of the pendulum of this clock are sent by electricity over the wires to the telegraph offices in Washington and New York. When the telegraph operators hear this sound on their instruments they know that the noon signal is about to be sent out, and they at once begin to connect the telegraph wires with other towns and cities, until in a minute or two the "tick, tick" of the clock at Washington is heard in hundreds of telegraph offices. The beats stop at ten seconds before twelve as a notice that the next "tick" will be the noon signal, and so as to give the operators time to connect their wires with the standard time-balls and clocks. There are time-balls in a great many cities—usually on top of some prominent building, where they can easily be seen. The one at Washington is on the roof of the State, War, and Navy Department Building, at the top of a high pole, ready to drop the instant the signal comes over the wire. In the government offices at Washington and in many places in other cities there are large clocks connected with the observatory by electricity. These are so arranged that when the twelve-o'clock signal is flashed over the wires, the hands of each one of these clocks spring to twelve, no matter what time the clock may show; in this way hundreds of clocks are set to the correct time each day.
Well, the moment the sun is supposed to cross the seventy-fifth meridian, the telegraph instruments give a single tick, the time-balls drop, the clocks begin to strike, and everybody in the district knows it is twelve o'clock.
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