PREF A^OE. 
Ever since his memorable journey through the canons of the Colorado 
River it has been Major Powell’s intention to write a description of the 
region adjacent to the Grand Canon and to discuss its geological problems. 
It is to be regretted that other duties have prevented him. There is no one 
so well fitted for it, and his right to do so is virtually prescriptive. But 
the time and opportunity never came to him. When Mr. King assumed 
the Directorship of the Survey he acceded to Major Powell’s desire to have 
the work in the Grand Canon district prosecuted, and, in accordance with 
the wishes of the latter, I was assigned to the immediate charge of it. 
Much of it was familiar ground. During the seasons spent in the study of 
the High Plateaus I had found the temptation irresistible to wander far 
outside of the limits of my j:)rescribed field; and whither should the errant 
geologist turn his footsteps so eagerly as towards the wonder-land of the 
south'? And so, when the early snows and biting winds of autumn drove 
us out of the lofty volcanic regions of the north, the remaining weeks of 
each year were spent in rapid excursions through the milder regions which 
lie beyond the foot of the great stairway of terraces which leads down 
from the heights of the Markdgunt. 
In the summer of 1879 Messrs. Bodfish and Renshawe were employed 
in making detail maps of more than ordinary accuracy, the former in the 
Kaibab, the latter in the Uinkaret. Mr. Renshawe completed his field 
work that season and finished his map in the office the following winter. 
But Mr. Bodfish’s work was much more extensive and difficult, requiring 
(vii) 
