STANDARD TIME IN THE UNITED STATES. 179 



If by any mischance the ball does not so fall at noon, it is kept up 

 to its place until IS*" 5 0', when it is dropped. To signalize this pro- 

 gramme, which may occasionally be necessary, a small flag marked 

 12'' 5"" will be at once hoisted, and kept flying till the ball is dropped. 

 A ball of this size can be seen by every vessel lying at the wharves 

 of Brooklyn and New York, either in the North or East River, and 

 by every vessel in the bay, even beyond Quarantine, if the ordinary 

 night-glass is employed. 



At the instant of the fall their chronometers should indicate 

 4'' 56" 1.65' (Greenwich time), and the difierence between this time 

 and what their chronometers really give is the correction to them. 

 Daily observations of the fall of this ball will give the daily gain or 

 loss of the chronometers ; that is, their rates, 



A capital advantage will be that such corrections and rates can be 

 determined without removing the chronometer from the ship, so that 

 a fertile source of disturbance which accompanies the carriage of the 

 chronometer to and from the vessel is thus, in future, avoidable. To 

 the citizens of New York and Brooklyn the ball is widely visible. It 

 can be seen on Broadway from Grace Church nearly to the Battery, 

 and a suitable position can be found nearly anywhere in the city from 

 which its face can be observed. 



Incidental to this programme, and as an immediate consequence of 

 it, the means of securing an accurate agreement of clocks throughout 

 the city is at hand. The Western Union Company will agree to con- 

 trol electrically other clocks in New York City and vicinity, so that 

 they shall constantly indicate the standard time. One means of 

 doing this is so simple that it deserves mention. Each clock to 

 be so controlled has an attachment contrived so that when its hands 

 arrive at the position 12'' 0" m., a small pin is thrown out through a 

 hole in the clock-face just in front of the minute-hand, which is thus 

 held fast at twelve o'clock. The outer end of the hand is held fast, 

 but the axis on which the inner end is placed keeps on turning, so that 

 the clock-train is not interfered with. This is the mechanical arrange- 

 ment. The practical working of the system is as follows : Each clock 

 is regulated so as to gain from ten to thirty seconds daily ; therefore, 

 when its hands reach noon, it is not really noon, but lacks from ten 

 to thirty seconds of it. The pin is protruded, and fastens the minute- 

 hand in its place till it is withdrawn by an electric signal from the 

 regulating or motor clock, and then all the hands start together, and 

 continue to move for twenty-four hours, gaining their ten or twenty 

 seconds in time for a repetition of the process on the next day. This 

 beautiful and simple device, invented by Bain, has another advantage 

 that of cheapness for it requires the use of the wire from the con- 

 trolling clock but for an instant each day, and, in a crowded city like 

 New York, the expense of erecting and maintaining the necessary tele- 

 graphic wire from each clock to the controlling clock is a minimum. 



