Each lighthouse in Australia has its own unique timing sequence, and Cape Leeuwin Lighthouse flashes every 7.5 seconds. So, let's say you had sailed from England, down the west coast of Africa, past the treacherous waters of the Cape of Good Hope then across the Indian Ocean on the Roaring Forties. You hadn't seen land for weeks. When you first sight land you count the timing sequence of the lighthouse and check your navigation charts, working out that you're at Cape Leeuwin. Further north Cape