CAMP DRUM, November 26, 1863.

Lieutenant Colonel JAMES F. CURTIS,

Commanding Southern District of California:

SIR: I have the honor to report that at 8 p. m. of the 22nd instant I arrived at Fisherman's Harbor, Island of California, with two enlisted men of Company C, Fourth Regiment Infantry California Volunteers, having sailed from the port of san Pedro on the sloop ned Beal, burden 17 28/100 tons, owned by Spencer W. Wilson, of Wilson's Harbor, Island of Catalina, John Brown, master, at 1 p. m. of the same day, in compliance with the following instructions, to wit:

HEADQUARTERS DISTRICT OF SOUTHERN CALIFORNIA,
Camp Drum, November 21, 1863.

Major HENRY HANCOCK,

Fourth California Infantry, Camp Drum:

MAJOR: In view of the probability that the neighboring island, Catalina, may soon be of commercial importance, you will proceed there to-morrow and obtain such information as can speedily be had of its resources and advantages as a military point. The harbor upon its westerly side will claim your best attention. Ascertain its extent, scan well its surrounding points, and learn by whom, if at all, the lands adjoining the harbor are occupied. You will make report to these headquarters as soon as is possible.

Very respectfully, your obedient servant,

JAMES F. CURTIS,

Lieutenant-Colonel, Commanding.

The population of the island is about 100, one-half of whom are miners, who perhaps with much reason entertain highly exalted views of the vastness of its mineral wealth, and from my personal examination of various lodes of argentiferous galena, the indications, it is clear to me that the surface indications of numerous discoveries are indeed of the most flattering promise, and should the discoveries made and daily being made prove to be regular metallic veins in lieu of eruptive masses of metal, the mines of the island will very soon yield immense quantities of silver, lead, and some gold, for the latter has been found there in quartz. Aside from the mines, grazing is the principal avocation of the inahbitants. The present number of sheep is about 15,000, 9,000 of which belong to Mr. Spencer W. Wilson. Of goats there are some 7,000 or 8,000. Of cattle and horses there are not many. The island, in the main, is too rough and dry for agricultural pursuits. Although there is no abundance of wood and water, the supply of both is adequate to all present and perhaps future demands. The length of the island is twenty-three miles, nearly divided by a narrow isthumus, on the south side of which the averge width of the island is about eight miles, and on the north some four miles. The shores are studded with numerous little harbors, the principal one of which is the Isthmus Harobor, situated on the southwesterly or seaward side of the island, and following around the south end on the same side is Little Harbor, some three miles distant, and on the northeasterly or land side are Goat Harbor, Pot Hole Harbor, Cherry Valley Harbor, Fisherman's Harbor, the anchorage or bay on the northeaster side of the isthumus, Fourth of July Harbor, from which two miles and a half farther on is the Harbor at the mouth of Howland's Valley (from which at this time some thirty miners residing at the Fourth of July Harobr take their waterin casks by skiffs), and in less than a mile farther on is Wilson's, or the old John Beghn Harobr, as also others of minor importance, in continuation around to the principal one of the island first named. These several harobrs abound with fish of excellent quality, among which are found the rock cod and mackerel. The latter are caught and have to a limtied extent become an article of commerce.