The cache is located in a beautiful and now serene part of Tasmania that holds a history that goes back to the penal system operating on the Tasman and Forestier Peninsula’s. Conical Hill was used as a manned semaphore station that was a part of the Port Arthur prison system communication network. The semaphore system provided communications around the Tasman and Forestier Peninsula’s to Port Arthur and Hobart Town.
The Conical Hill station was known as The Sounds signal station (No. 1722). It was named after King George Sound which the cache directly overlooks. Murdunna at the head of the Sound was the location of the Port Arthur prison slaughterhouse. A causeway and remnants from an old jetty remain where ships would collect their loads of meat.
The Sounds semaphore was erected in the early 1840’s. The Port Arthur military commandant who created the semaphore system, Captain Charles O’Hara Booth personally selected the station sites. He nearly died not far from here on the Forestier Peninsular when he became lost for 4 days in snowy weather suffering frostbite. His health never recovered from the ordeal.
Captain Booth records in his diary (published) that on 7 January 1834 he and his kangaroo dogs "Old Spring" and "Venus" had a very successful kangaroo and wallaby hunting trip at Comical Point and Comical Hill. It appears that Chronicle Point and Conical Hill have since had subtle name changes.
Most of the stations on the Tasman and Forestier Peninsula’s were operated by good-conduct convicts. The operators were liable to sudden removal at any time, as a security measure. Each station needed to be visible by at least 2 others in the chain.
The semaphore consisted of moveable arms attached to a tall mast that could send numerically coded messages. The code book used listed 3000 messages (e.g. convict absconded) and up to 999,999 numbers could be used. Long messages could be passed between Hobart Town and Port Arthur in a very short space of time. The semaphore network was closed down in 1849 and reactivated during the 1860’s.