Cook's Secret Instructions

On each of James Cook's three voyages to the South Pacific between 1768 and 1779 he carried 'Secret Instructions' issued by the Admiralty. They were secret in that they held the real intentions and plans for the voyage, while other papers issued would be made available on demand to show Cook's authority for his command and the enterprise. The secret instructions contained an outline of the route of the voyage, activities he and his men were to undertake, and the manner in which he was to report his progress.

Secret Instructions within the Letterbook carried aboard the Endeavour record the quest for scientific discovery, combined with the desire to find exploitable natural resources and to expand Britain's control of strategic trading posts around the globe. The Instructions confidently assume that these varied interests could be made compatible with a respect for the native populations in those countries so identified. They authorised Cook to take possession of, "a Continent or Land of great extent" thought to exist in southern latitudes and on the second page; "with the Consent of the Natives to take possession of Convenient Situations in the Country in the Name of the King of Great Britain".

After completing the scientific observation of the transit of Venus from Tahiti Cook followed Secret Instructions to sail to latitude 40* south in search of the fabled 'Great Southern Continent'. The Secret Instructions provided that, in the event that he found the Continent, he should chart its coasts, obtain information about its people, cultivate their friendship and alliance, and annex any convenient trading posts in the King's name.

Cook circumnavigated both the north and south islands of New Zealand thus disproving Abel Tasman's supposition that New Zealand formed part of the southern continent. He then turned west to find the southern coast of New Holland on April 20, 1770 and followed it north, landing at Botany Bay one week later, before continuing to chart the coast to the northern tip.

On Possession Island, just before sunset on August 22, 1770, he declared the coast a British possession:
"Notwithstand[ing] I had in the Name of His Majesty taken possession of several places upon this coast, I now once more hoisted English Coulers and in the Name of His Majesty King George the Third took possession of the whole Eastern Coast ... by the name New South Wales, together with all the Bays, Harbours Rivers and Islands situate upon the said coast, after which we fired three Volleys of small Arms which were Answerd by the like number from the Ship".

Cook had recorded signs that the coast was inhabited during the voyage north, and here he noted as he returned to the ship the great number of fires on all the land and islands about them, 'a certain sign they are Inhabited'.

The six page Letterbook carried aboard the Endeavour, still in its original marbled paper cover,  is held in the National Library of Australia and contains the only surviving set of Cook's original Secret Instructions.