Yours cordially, J.W.

Powell.
In complying with this request to put on record the second expedition and the gentlemen who composed it, I feel all the greater pleasure, because, at the same time, I seem to be fulfilling a duty towards my old comrades.

The reader is referred to Chapter XIV., and to pages 368-9 for later data on descents.

Notwithstanding these the canyons remain almost terra incognita for each new navigator.

There have been some who appear to be inclined to withhold from Major Powell the full credit which is his for solving the great problem of the Southwest, and who, therefore, make much of the flimsy story of White, and even assume on faint evidence that others fathomed the mystery even before White.