APPENDIX B. 
REPORT UPON THE ROUTE PROM SAN BIEGO TO PORT YUMA, VIA 
SAN DIEGO RIVER, WARNER’S PASS, AND SAN PELIPE CANON. 
BY CHARLES H. POOLE, 
CHIEF ENGINEER. 
San Diego, California, October 10, 1855. 
Dear Sir: I have the honor herewith to submit to you, in compliance with the request com¬ 
municated to me at the time of your departure from California, the following report of the 
results obtained of a survey by me of the proposed route for a railway across the State of Cali¬ 
fornia, and between the port of San Diego and the mouth of the river Gila. This survey, as 
you are aware, was undertaken by the company organized at this place under the laws of the 
State of California for the purposes of insuring a careful and minute examination of passes in 
the Coast mountains believed-to be practicable and adapted to the passage of a railroad. 
The exploration was deemed more necessary and important, from the fact that the limited 
time allowed to Lieutenant Williamson for his examinations last year did not permit so close a 
survey of the country between the coast and the Colorado river as the very peculiar and difficult 
nature of the country seemed to require. It was believed essential that the acknowledged 
advantages of a terminus of the Pacific coast within 200 miles of the mouth of the Gila, at a 
port and harbor of unrivalled excellence, should not lightly be passed over in these preliminary 
examinations, nor suffered to be neglected for want of adequate information as to its practica¬ 
bility of access. 
TOPOGRAPHY OF THE COUNTRY. 
It will be proper to give a brief statement of the main features of the district proposed to be 
traversed by the railroad, in order to insure a correct understanding of the objects, details, and 
results of the survey. 
The Pacific coast, from San Diego to San Pedro, a distance of 100 miles, has a general direc¬ 
tion northwest, unbroken by any cove or inlet, presenting a continuous series of bluffs and 
narrow valleys, formed by the spurs and foot-hills of the mountains of the interior, which, as 
they approach the sea, gradually subside into rolling and sometimes abrupt ridges divided by 
water-courses tending to the ocean. About fifty miles from the sea, the Coast or Cordilleras 
range of mountains extend nearly parallel with the coast from their junction with, or rather 
their disjunction from, the Sierra Nevada, entirely across the district and through Lower Cali-, 
fornia to Cape St. Lucas. The divide or watershed of these mountains is not a direct line of 
