Atlantic Islands

Several Atlantic islands were important as locations on trade routes for sailing ships. Many were occupied by European powers or trading companies. One of the earliest time balls was established on St Helena in 1834 by the British East India Company, shortly before St Helena became a British Colony. It was complemented initially by a time gun and a repeater ball, following early use of rocket signals. The original observatory was closed in 1836 and a new time ball was erected at a lower level, with retention of the repeater ball. They continued operation into the twentieth century. A time ball had existed on Ascension up to at least 1865. Most islands under jurisdiction by Spain and Portugal offered telegraph time signals that could be accessed for chronometer calibration. Light signals were introduced from 1914 on three islands in the Azores. Time balls were introduced in the Cape Verde Islands in the 1920s.