The record of the first expedition is one of heroic daring, and it demonstrated that the river could be descended throughout in boats, but unforeseen obstacles prevented the acquisition of scientific data which ours was specially planned to secure in the light of the former developments.

The map, the hypsometric and hydrographic data, the geologic sections and geologic data, the photographs, ethnography, and indeed about all the first information concerning the drainage area in question were the results of the labours of the second expedition.

Owing, perhaps, to Major Powell's considering our work merely in the line of routine survey, no special record, as mentioned above, was ever made of the second expedition.

We inherited from the first a plat of the river itself down to the mouth of the Paria, which, according to Professor Thompson, was fairly good, but we did not rely on it; from the mouth of the Paria to Catastrophe Rapid, the point below Diamond Creek where the Howlands and Dunn separated from the boat party, a plat that was broken in places.

This was approximately correct as far as Kanab Canyon, though not so good as above the Paria.
From the Kanab Canyon, where we ended our work with the boats, to the mouth of the Virgin we received fragments of the course owing to the mistake made in dividing the notes at the time of the separation; a division decided on because each group thought the other doomed to destruction.