By degrees he shaped his vague day-dream into a practical reality.  Having made himself acquainted with all the requisites for a trading enterprise beyond the mountains, he determined to undertake it.  A leave of absence, and a sanction of his expedition, was obtained from the major general in chief, on his offering to combine public utility with his private projects, and to collect statistical information for the War Department concerning the wild countries and wild tribes he might visit in the course of his journeyings.

Nothing now was wanting to the darling project of the captain, but the ways and means.  The expedition would require an outfit of many thousand dollars; a staggering obstacle to a soldier, whose capital is seldom any thing more than his sword.  Full of that buoyant hope, however, which belongs to the sanguine temperament, he repaired to New-York, the great focus of American enterprise, where there are always funds ready for any scheme, however chimerical or romantic.  Here he had the good fortune to meet with a gentleman of high respectability and influence, who had been his associate in boyhood, and who cherished a schoolfellow friendship for him.  He took a general interest in the scheme of the captain; introduced him to commercial men of his acquaintance, and in a little while an association was formed, and the necessary funds were raised to carry the proposed measure into effect.  One of the most efficient persons in this association was Mr. Alfred Seton, who, when quite a youth, had accompanied one of the expeditions sent out by Mr. Astor to his commercial establishments on the Columbia, and had distinguished himself by his activity and courage at one of the interior posts.  Mr. Seton was one of the American youths who were at Astoria at the time of its surrender to the British, and who manifested such grief and indignation at seeing the flag of their country hauled down.  The hope of seeing that flag once more planted on the shores of the Columbia, may have entered into his motives for engaging in the present enterprise.

Thus backed and provided, Captain Bonneville undertook his expedition into the Far West, and was soon beyond the Rocky Mountains.  Year after year elapsed without his return.  The term of his leave of absence expired, yet no report was made of him at head quarters at Washington.  He was considered virtually dead or lost and his name was stricken from the army list.

It was in the autumn of 1835 at the country seat of Mr. John Jacob Astor, at Hellgate, that I first met with Captain Bonneville He was then just returned from a residence of upwards of three years among the mountains, and was on his way to report himself at head quarters, in the hopes of being reinstated in the service.  From all that I could learn, his wanderings in the wilderness though they had gratified his curiosity and his love of adventure had not much benefited his fortunes.  Like Corporal Trim in his campaigns, he had “satisfied the sentiment,” and that was all.  In fact, he was too much of the frank, freehearted soldier, and had inherited too much of his father’s temperament, to make a scheming trapper, or a thrifty bargainer.