They ascended the Missouri, passed through the stupendous gates of the Rocky Mountains, hitherto unknown to white men; discovered and explored the upper waters of the Columbia, and followed that river down to its mouth, where their countryman, Gray, had anchored about twelve years previously.

Here they passed the winter, and returned across the mountains in the following spring.

The reports published by them of their expedition demonstrated the practicability of establishing a line of communication across the continent, from the Atlantic to the Pacific Ocean.
It was then that the idea presented itself to the mind of Mr.Astor, of grasping with his individual hand this great enterprise, which for years had been dubiously yet desirously contemplated by powerful associations and maternal governments.

For some time he revolved the idea in his mind, gradually extending and maturing his plans as his means of executing them augmented.

The main feature of his scheme was to establish a line of trading posts along the Missouri and the Columbia, to the mouth of the latter, where was to be founded the chief trading house or mart.