At the beginning of XIX century, coincided with the rapid development of technological progress, the problem of storage time faced postal services, attempting to ensure the movement of postal crews on schedule. As a result, they got vozimymi clock. And with the advent of railways hours received at their disposal, and conductors. The more developed the transatlantic communication, the urgent problem of ensuring the unity of timing on different sides of the ocean. In this situation vozimye clock is not a century. And then came to the aid of electricity, in those days called galvanism. Electric hours solved the problem of synchronization over long distances - at first on the mainland, and then between them. In 1851 cable, which formed at the bottom of English Channel, in the 1860-meters - the Mediterranean Sea, and in the 1865-meters - the Atlantic Ocean. And since 1899 began the era of signals of exact time on the radio.

At the initial stage of development of electric clock electric power only served to plant the leading mechanical devices - the goods or springs. Electric clocks, significantly different from the classic gear, designed the Englishman Alexander Bain, the inventor of an electromechanical telegraph. In 1840 he received a patent for the electric clock, the main parts of which were conventional mechanical contained a spring, but the indicator has been already established in the sum of electrical pulses, filed pendulum clock. By 1847 Bain has completed work on a truly electric clock, the heart has been contact, driven pendulum, swinging electromagnets. Fluctuations fold electromagnetic meter connected wheel transmission arrow on the dial.

At the beginning of XX century electric clock finally replaced the mechanical systems of storage and transfer of accurate time. The most accurate clock, based on free electromagnetic pendulum clocks were William Shortta established in 1921 in Edinburgh Observatory. From the monitoring of the three hours Shortta manufactured in 1924, 1926 and 1927 years in the Greenwich Observatory, to determine their average error of 1 / 300 s, which corresponds to 1 second error in the year. Accuracy of hours with a free pendulum Shortta allowed to detect changes in the length of the day. And in 1931 began a review of absolute units of time - time the star, taking into account the motion of the Earth's axis. This error, which until then had been neglected, reaching its maximum of 0,003 seconds per day. A new unit of time was later named the Middle stellar time. Accuracy Shortta hours was unsurpassed until the appearance of quartz watches.