HYDROGRAPHIC REPORT, 
scien 
Nore.—Throughout this report, in stating facts bearing upon the navigability of the Colorado, the river is described as it 
appeared at its lowest and worst stage. It is probable, however, that not once in twenty years would the navigation be 
attended with so many obstructions as during the season of unprecedentedly low water when the survey was made.] 
GULF OF CALIFORNIA AND MOUTH OF THE COLORADO. 
The Gulf of California, into which the Colorado river empties, is six hundred miles long, and 
averages about eighty miles in width. The navigation is good, particularly along the western - 
or Lower California shore, where the coast is bold and rock-bound, and the water deep. 
Along the northern half of the eastern side the country is generally low, and the adjacent 
soundings shallow. 
The surface of the Gulf is dotted with islands, some of which are twenty or thirty miles in 
extent. The faces of these islands are usually precipitous, and there are many, in the lower 
part of the Gulf, where, to the very base of the cliffs, there are nosoundings. As the lead would 
not give notice of their proximity, during dark nights, unless caution was observed, their 
neighborhood might be attended with hazard. There are no currents that prove a hindrance 
to navigation. Between the islands and along the shore, particularly near the head of the 
Gulf, the tides are sometimes strongly felt. 
The prevailing winds blow either up or down the Gulf. During the autumn and winter 
they are generally from the northwest. In summer southeast breezes are more frequent. The 
worst gales come from this quarter. Calms are liable to be encountered at all seasons. In the 
vicinity of Cape St. Lucas, which is at the southern extremity of Lower California, they occur 
oftenest and are of longest duration. It is in the same neighborhood that the most furious 
storms and tempests are experienced. The length of the voyages of sailing vessels from San 
Francisco to the mouth of the Colorado is from fifteen to thirty-five days. 
The greater portion of the harbors is upon the coast of Lower California. They are at Cape 
St. Lucas, San José, La Paz, Port Escondido, Loreto, Molega, Angeles bay, San Louis, and 
the bay of San Felipe. At Cape St. Lucas harbor there is sufficient depth for vessels of the 
heaviest draught. The harbor is protected from southeast winds, but is exposed towards the 
north and west. It isa dangerous anchorage, for there is a high surf, and no bottom at a 
hundred fathoms, t‘ll within a short distance of the beach. The locality can be distinguished 
a long distance off by the white cliffs that border the coast. At San José the harbor is exposed 
_ from east northeast to southwest, and would be unsafe during the summer and early autumn. 
The holding ground is good. The harbor of La Paz is land-locked, but vessels of large size 
cannot approach within three miles of the town. At Loreto, Port Escondido, Molega, a little 
beyond Point Conception, and at Angeles bay vessels of moderate draught can find a good 
anchorage. Angeles bay has been seldom resorted to. It is towards the head of the Gulf, and not 
far from the southwestern extremity of Angeles island. It is four miles wide and opens towards 
the east.. There are springs of slightly brackish water near the southern end, at the base of 
a high mountain. An excellent bed of oysters exists in the vicinity. There are said to be 
mines in a valley at no great distance. At San Louis and San Felipe there is anchorage 
for small vessels. The latter place is only fifty miles from the mouth of the Colorado. 
