The mining region is constantly increasing in extent. The _placers_ first worked still yield a profit sufficient to reward the gold seeker for his labor, and the frequent discovery of new ones by parties prospecting, keeps up the heat of excitement. The region is constantly extending towards the north. The vicinity of Trinity River is the most northern part of California where gold is obtained in any considerable quantity, and the source of the San Joaquin, is the most southern. The entire region embraced between these two points is known to abound in the precious metal, and is traversed by the gold "prospecters." Of the gold obtained, a great quantity--a third, at least, remains in the country. Another is carried out of California by the foreigners, and the remainder is sent to the Atlantic States of the Union. This is but a rough estimate; but it seems warranted by the facts of the number of foreigners in the country, and the necessary current money of the residents. Certain it is, that were we to judge of the quantity of gold obtained in California, by the amount received in the United States, we would fall far too short of the truth. The growth of the commerce of California necessarily carries with it the growth of all those cities and towns which have any commercial advantages, or which are connected with the various ports. Not only has San Francisco constantly in her harbor a tremendous fleet of merchant vessels from all parts of the world, pouring into her lap the commodities necessary to a new country and a rapid building city, and Sacramento, the commerce of the mines continually passing through it, but all the towns along the coast have felt the impulse, and have become the seat of a traffic of some sort. San Diego, Santa Barbara, San Pedro, and Monterey, are all commercial ports, which have become the resort of those traders who wish to escape the crowd of competitors to be met with at the more northern towns, and to have a pleasant place of residence besides. Los Angeles, twenty-five miles from the port of San Pedro is the centre of an extensive inland trade, and from its being a delightful place of residence, will contribute to the building up of San Pedro in a greater degree than the commerce of San Pedro can influence it.