17 June 2008 - Fremantle - The Timeball & Gun - Arthur Head Fremantle. I hope you can see the faded sepia photo on the right - the Time Ball is on the left of the light house, each structure is on top of the limestone wall that the Round House was built on where the whalers tunnel is underneath - got that??? Hope so. Anyway, this Timeball is fascinating. Hope you are interested because here is the story. Ports all around the world provided a method for ships to obtain an accurate time so they were able to rate their chronometers. The correct time on the chronometer, a ship's clock, was necessary so the crew could establish their exact longitude, a necessity when following their charts. Each ship had two chronometers, one set on Greewhich Mean Time and the other to calculate the local time. A plan for a time ball was drawn up in 1899 and then built in 1900 on Arthur Head. In 1902 a time gun was incorporated into the signal station. This meant they had a sound signal as well as a line of sight. The line of sight was necessary because the slowness of sound meant it would not have been exactly 1:00 pm when it was heard. The timeball structure had a second story tower with a signal mast above. A cane signal ball was attached to this mast and on the balcony around the tower was a hanging bracket. Prior to 1:00pm each working day (Mon to Fri) an employee of the Harbour would affix one and a half sticks of gelignite to power leads to the hanging bracket then at 3 minutes to 1:00pm use a windlass to raise the ball to the masthead. Arrangements were made with the Perth Observatory so that the 1:00pm signal could be diverted from Fremantle Railway Station to the tower. The observatory at that time sent signals to railway stations every hour. The time signal was discontinued on 17 November 1936 as radiotelegraphy had superseded it. Pretty neat hey...
