160 FORT YUMA 
shutting off the view of the desert. On the north and 
west the line of the desert is perceived at a distance 
of about three miles, this line of view being inter- 
rupted by the isolated mountain called ‘ Pilot Knob.” 
At the south, short isolated ridges of mountains are 
seen at a great distance. Mr. Pratt took a panoramic 
view of the country here, which will convey a better 
idea than any description I can give. 
The Gila was not over fifty yards wide at its mouth ; 
but its width varies much in different seasons, being 
influenced by the rise of the Colorado, as well as the 
state of its own waters. The Colorado was now so high 
as to cause the Gila to flow back full fifteen miles. 
The Gila was still low, and, except near the junction, 
but a diminutive stream. It is doubtful whether it 
can ever be navigated, except at its floods, and these 
are by no means regular. At such times flat-bottomed 
boats might pass to the mouth of the Salinas, near 
the Pimo villages. 
The singular bend which the Colorado takes after 
it receives the Gila, gives to the United States both its 
banks for the distance of seven miles from the junction, 
or to the point where it resumes its southerly course. 
This arises from the stipulations of the fifth article of the 
treaty with Mexico defining the boundary line, which 
says, that ‘‘a straight line shall be drawn from the mid- 
dle of the Rio Gila, where it unites with the Colorado, 
to a point on the coast of the Pacific Ocean, distant one 
marine league due south of the southernmost point of 
the port of San Diego.” The land on the southern bank 
of the Colorado which we thereby obtain is of little value 
for agricultural purposes; but should a considerable 
