In 1764 he was made naval engineer for Newfoundland and Labrador, and was employed for three consecutive years in hydrographical tasks, which obtained for him the notice of the ministry, and helped to correct innumerable errors in the maps of America. At the same time he addressed a treatise to the Royal Society of London, upon an eclipse of the sun, which he had observed in Newfoundland in 1766. This document appeared in the "Philosophical Transactions." Cook was not long in receiving a due reward for so much, and such successful labour, and for his patient studies, the more meritorious, as he had had few opportunities, and was self-taught. A scientific question of the highest importance, viz., the transit of Venus across the sun's disc, which had been announced for 1769, was eagerly discussed by all the scientists of the day. The English Government, confident that this observation could only be effectually made in the Pacific Sea, resolved to send a scientific expedition thither. The command was offered to the famous hydrographer A. Dalrymple, equally celebrated for his astronomical investigations, and his geographical discoveries in the southern seas. But he was so exacting in his demands, and so persevering in his request for a commission as ship's captain, which Sir Edward Hawker as obstinately refused, that the Secretary of the Admiralty proposed another commander for the projected enterprise. His choice fell upon James Cook, who was cordially recommended by Sir Hugh Palliser, and to him therefore the command of the _Endeavour_ was given, whilst he was at the same time raised to the rank of ship's lieutenant. Cook was now forty years of age. This was his first appointment in the Royal Navy. The mission entrusted to him called for varied qualifications, rarely to be met with in a sailor. For, although the observation of the transit of Venus was the principal object of the voyage, it was by no means the only one. Cook was also to make a voyage of discovery in the Pacific Ocean. But the humbly born Yorkshire lad was destined to prove himself equal to his task. Whilst the _Endeavour_ was being equipped, her crew of eighty-four men chosen, her store of eighteen months' provision embarked, her ten guns and twelve swivel guns, with the needful ammunition, shipped, Captain Wallis arrived in England. He had accomplished his voyage round the world. He was consulted as to the best spot for the observation of the transit of Venus, and he selected an island which he had discovered, and which was named by him after George III. It was later known by its native name of Tahiti. From this spot therefore Cook was to take observations.