One other set of instructions from the Admiralty is of great importance in view of what subsequently occurred, and had a bearing upon the expedition as it affected political relations. Great Britain was at war with France, and the Investigator, though on a peaceful mission, was a sloop belonging to the British navy. Flinders wrote to the Admiralty (July 2) soliciting instructions as to what he was to do in case he met French vessels at sea, "for without an order to desist, the articles of war will oblige me to act inimically to them." The directions that he received were explicit. He was to act towards any French ship "as if the two countries were not at war; and with respect to the ships and vessels of other powers with which this country is at war, you are to avoid, if possible, having any communication with them; and not to take letters or packets other than such as you may receive from this office or the office of his Majesty's Secretary of State." The concluding words of the instruction intimately concern the events which, in the next year but one, commenced that long agony of imprisonment which Flinders had to endure in Ile-de-France. He was also provided with a passport from the French Government, and the terms in which it was couched are of the utmost importance for the understanding of what followed. It was issued for the Investigator, commanded by Captain Matthew Flinders, for a voyage of discovery of which the object was to extend human knowledge and promote the progress of nautical science. It commanded all French officers, at sea or on shore, not to interfere with the ship and its officers, but on the contrary to assist them if they needed help. But this treatment was only to be extended as long as the Investigator did not announce her intention of committing any act of hostility against the French Republic and her allies, did not render assistance to her enemies, and did not traffic in merchandise or contraband goods. The passport was signed by the French Minister of Marine and Colonies, Forfait, on behalf of the First Consul.* (* A transcript of Flinders' own copy of the French passport is now at Caen, amongst the Decaen Papers Volume 84 page 133.)