Douglass's vessel, the Iphigenia, was in serious need of supplies and assistance, which Gray generously furnished. Later he not only made to the northward a successful trading trip, but in the following year, in June, 1789, explored the whole east coast of Queen Charlotte Islands, to which he gave the name of Washington Islands, in honor of General Washington, then President of the United States. In another trading excursion from Nootka Sound, Vancouver Island, Gray entered the broad opening southeast of the island and sailed to the east-southeast fifty miles, where he found the passage still five leagues wide. This opening was the Straits of Fuca, and the first authentic exploration of the strait is the account of Gray. The credit of first passing through the entire length of the Straits of Fuca is due to Kendrick, who made the passage in the sloop Washington, after the departure of Gray to China on the Columbia. The account of the passage of the Washington through the Straits of Fuca was especially called to Vancouver's attention by the British Admiralty on the occasion of his surveying voyage of 1791, when he was particularly to "examine the supposed Strait of Juan de Fuca, said to be situated between the forty-eighth and forty-ninth north latitude, and to lead to an opening through which the sloop Washington was reported to have passed in 1789, and to have come out again to the northward of Nootka." Vancouver later denied to Americans the credit of first sailing entirely through the Straits of Fuca, resting his opinion on Gray's statement that he sailed only fifty miles within it, which was true; the credit belonging to Kendrick in his voyage with the Washington after Gray's departure from the coast in 1789. The efforts of Kendrick and Gray resulted in the obtaining of a full cargo of furs, which in accordance with their instructions were to be sold in China. Kendrick, fascinated with the prospects of fortune and success, and perhaps reluctant to face his owners owing to his lack of caution which resulted in the unfortunate killing of some thirty natives, decided to remain on the northwest coast, his imaginary Eldorado. Gray consequently transferred to the Columbia and set sail for Canton, then the great fur mart of the world. His voyage across the Pacific was prosperous, his furs were readily sold, and after taking a cargo of tea on board, Gray sailed for the Cape of Good Hope, and on the 10th of August, 1790, the Columbia entered the port of Boston, the first vessel to circumnavigate the world under the flag of the United States. His success and conduct so impressed the owners of the ship that they immediately decided upon sending Gray back to the northwest coast, and seven weeks later, September 28, 1790, he sailed in the Columbia, which was described as a ship of two hundred and twelve tons, manned by thirty men, and equipped with an armament of ten guns.