Once within the parallels of the Trade-wind, every other natural phenomenon is found to give way before that grand commotion of the atmosphere. Therein does nature constantly seek—according to Lieutenant Maury's happy generalization—to restore to the air that moisture which was forcibly abstracted by the cold of the Polar circle; in order to be enabled, on passing into the opposite hemisphere, to distribute genial showers. The region of these winds appears eminently one of mechanical energy; for, driven by all the tropical power of the sun, its “cumuloni” clouds are ever hurrying along overhead, while the swell of the ocean hastens after them below; growing as it goes, and curling into foam, agitating and suffering agitation in a continually increasing ratio.

So we found it on board Mr. Stephenson's good yacht Titania, as she winged her speedy way to Teneriffe, with her important freight of astronomical instruments, in the latter end of June and beginning of July, 1856.

Her beautifully-formed iron hull bounded over the waves as lightly as a pleasure skiff, and with far greater velocity. But how she did roll! in manner not disagreeably,—for a delicate digestion was not disturbed,—yet that the quantity was most notable, let twenty measured angles, of 15° to 20° each, per minute, sufficiently testify.