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Show PREDICTS HEIGHT OF TIDES One of the many duties undertaken by the United States coast and geodetic geo-detic survey, which furnishes official information about our sea coast and harbors for the use of mariners plying these waters, is that of predicting the tides at any given station at any time in the future. To gain this information informa-tion a new machine of a very complicated compli-cated nature hasjust been constructed by the bureau and placed in operation in the headquarters at Washington The tide levels for a year can be obtained ob-tained in from ten to fifteen hours for any station. To the layman the machine ma-chine appears to be a mass of little wheels, knobs, cranks, chains and glittering brass indicators, but the new superintendent of the bureau, Dr. E. Lester Jones, explains the functions of each part and finally arrives at the roll of paper on one end on which two fountain pens are drawing lines. One of these draws a line about the middle .of the roll which represents the mean sea level while the the other draws a varying line which represents the tide. From this graphic record, which is 370 feet long and about six inches wide, representing the tides for a year, the tide level at any time in that period can be readily ascertained. |