Engraved text: "Australia - Postmaster general Department To mark the finish of laying a coaxial cable from Sydney to Melbourne by Post Office Lines Staff. This stone was unveiled on 10th November 1961 by the Honourable O W Davidson OBE Mp, Postmaster General. The two cities were first linked by telegraph in 1858 and by telephone in 1907. Each pair of tubes of the 6 tube coaxial cable makes possible over 1000 simultaneous telephone or telegraph connections or transmission of two television programmes. The two inch cable was buried at a depth of 4 feet at an average rate of 12 miles a day."