27,600 feet. This is the greatest depth of the ocean that has yet been satisfactorily ascertained; but we have reason to believe there are many parts of it where it is still deeper. Its determination is another desideratum in terrestrial physics of great interest and importance.
The small island of Trinidad was at this time the nearest land to us; it bore S. 47 W., distant 486 miles. Cape Frio, the nearest part of the continent, bore S. 65 W., distant 1180 miles.
The temperature at twelve hundred fathoms was 39°.5; at nine hundred fathoms, 40°.3; that of the surface, 77°.
June 7.On the 7th we passed within a mile of Trinidad, but there was too much surf for us to attempt to land. On the 18th, at 4h 40m p.m., we anchored in the beautiful harbour of Rio. We regretted to find Commodore Purvis had gone to Monte Video, and, moreover, that all our letters had been forwarded to him there, contrary to his express orders. As we could not now get them in less than a month, and not choosing to lose so much time, I determined, as soon as we could complete our magnetic observations, to sail for England.
We found an American squadron lying here, under the command of Commodore Shubrick, upon whom Captain Crozier and I immediately called, and by whom, and his officers, we were most politely received. They had recently returned from Monte Video, the policy of their government not