The tour would lie through the valleys of the Miami of the lakes, and the Wabash, which interlock at the Fort Wayne summit; then across the Grand Prairie of the Illinois to St.Louis, and up the Illinois River from its mouth to its source.

This would give me a personal knowledge of three great valleys, which I had not before explored, and connect my former southern explorations in Arkansas and Missouri with those of the great lake basins and the upper Mississippi.

I had been at the sources and the mouth of that great river, and I had now the opportunity to complete the knowledge of its central portions.

It was with the utmost avidity, therefore, that I turned my face again towards the West.
Mr.Calhoun, who was written to on the subject, concurred in this plan, and extended the time for the completion of my geological report.
_Joint Work on the Scientific Results of the Expedition of 1820_ .-- General Cass, who had been written to, thus expresses himself on this subject:-- "Captain Douglass has informed me that you and he meditate a joint work, which shall comprise those objects, literary and scientific, which could not properly find a place in a diurnal narrative.

At what time is this work to appear, and what are its plan and objects?
My observations and inquiries respecting the Indians will lead me much further than I intended or expected.