In the early forties of the 20th century, Western Union has used the first time a commercial intercity microwave transmission system. In 1877, starting from September, New York City residents began to have the opportunity to check the time on clock with the "time ball", located on the roof of constructed in the same year a new corporate headquarters - Western Union Building. One of the common kinds of money transfer is a transfer via the international system of Western Union. In 1884 Western Union has become a joint-stock company and was brought to the stock exchange. The company has entered in the first American stock index Dow Jones.