Since war went out of fashion, many officers of the British navy have been employed in exploring seas, and surveying coasts, in different parts of the world, for the laudable purpose of facilitating navigation; and there would be little harm in supposing, that there might be as much glory in verifying the position and extent of a shoal or sunken rock, as in capturing an enemy's frigate. At all events, these surveying voyages furnish useful occupation, not unattended with danger; and they involve the necessity for a good deal of hard work, of a dry and technical character, three years being the time usually allotted to a cruise. Australia, owing to the dangerous character of its northern and eastern shores, has been the scene of numerous surveys, among the latest of which was that by Captain Blackwood in the _Fly_. One important result of this survey was the finding of a passage through the great Barrier Reef for vessels navigating Torres Strait; but as more than one passage was considered essential to the safety of a route so much frequented, the _Rattlesnake_ was commissioned, in September 1846, for a further survey, to be carried on in what is called the Coral Sea, having New Guinea, the Louisiade Archipelago, and the continent of Australia, as its boundaries.[3] After some months spent in preliminary examination of different parts of the Australian shores and seas, the _Rattlesnake_ sailed from Sydney, at the end of April 1848, for the main object of her cruise. She had the _Bramble_, a small schooner, as tender, and was accompanied by the _Tam o' Shanter_, a vessel chartered for the conveyance of Mr Kennedy's expedition, which was to land at Rockingham Bay, 1200 miles to the northward, 'and explore the country to the eastward of the dividing range, running along the north-east coast of Australia, at a variable distance from the shore, and terminating at Cape York.' Having assisted in landing this party, and arranged to meet them at the head of Princess Charlotte's Bay, on their toilsome, and, as it proved, disastrous overland journey, the ships pursued their route, and soon commenced a series of triangulations, which were continued without a break for more than 600 miles. The _Bramble_ waited ten days at the appointed rendezvous without seeing anything of the overland expedition, which, as it afterwards appeared, did not reach the same latitude until two months later, and then at a considerable distance from the coast.