As written in the 1889 publication History of the Pacific Northwest Oregon and Washington 1889:
In the summer of 1839, the little handful of Americans in the Willamette valley experienced extreme solicitude, upon the appearance in the Columbia river of a British surveying expedition, commanded by Captain Sir Edward Belcher, Royal Navy. It consisted of her Majesty's ship Sulphur, 380 tons, with a complement of 109 men, attended by her Majesty's schooner Starling, of 109 tons, Lieutenant H. Kellett, Royal Navy, commanding.
This expedition for the survey of the Pacific coast, from Valparaiso to sixty degrees, thirty-one minutes north, and originally under command of Captain F.N. Beachey, R.N., had sailed from Plymouth, England, December 24, 1835. On reaching Valparaiso, Captain Beachey, in consequence of hill health, was compelled to return to England. Lieutenant Kellett commanded until January, 1837, at which time Captain Belcher joined the Sulphur at Panama. Nor were the jealous fears of these American settlers without occasion. Among the instructions by the British Admiralty, dated December 19, 1835, was the following:
"Political circumstances have invested the Columbia river with so much importance, that it will be well to devote some time to its bar and channels of approach, as well as to its anchorage and shores."
From a narrative of the voyage by Sir Edward Belcher, we quote the following extracts:
"On the 28th of July, 1839, H.B.M. ship Sulphur reached the mouth of the Columbia river, when Lieutenant Kellett, having descried us, weighed and stood with the Starling to conduct us in."
"On the 9th of August, after being nearly devoured by mosquitoes, we reached Fort Vancouver, where we were very kindly received by Mr. Douglas, and had apartments allotted to us."
The instructions of the British government in fitting out this surveying expedition clearly foreshadowed the british programme of acquiring Oregon by acts of occupancy. It is evident that the territory north of the Columbia was deemed British soil. Captain Belcher numbers the American element in Oregon as "twenty American stragglers from California, ten clergymen, teachers, etc., American Methodist Mission and four missionary stations in the interior." British feeling against these whom they regarded as trespassers and intruders, who are denounced as "stragglers," is faithfully portrayed in Belcher's narrative. It is a British view of Oregon in the fall of 1839, and indicates the situation of the pioneers, - their duties, their dangers, their responsibilities, their outlook of the future.