Known locally as the “Sentinel of Semaphore,” the Time Ball Tower was built in 1875. Other similar towers set up in cities around the world, the first being built at Greenwich in the United Kingdom in 1833. The solid stone structure features a black ball that dropped at 1 p.m. every day, signaling ships to rate their chronometers that are used as vital navigation instruments. The Semaphore Time Ball Tower was built by Henry Burge. The stone tower featured a ball measuring about five feet in diameter, large enough to be visible to…