Humboldt, at Caraccas, in South America, has made ſome intereſting obſervations on the motion of the barometer near the equator.

“I have read,” ſays he, “in the tranſactions of the Bengal ſociety, that the barometer riſes and falls there regularly every twenty-four hours.

Here, in South America, its motion is more aſtoniſhing.

There are four atmoſpherical tides every twenty-four hours, which depend only on the attraction of the ſun.

The mercury falls from nine o’clock in the morning till four o’clock in the evening.

It riſes from four till eleven o’clock; it falls from eleven o’clock till half paſt four in the morning; it reaſcends, from that time till nine o’clock: neither winds, ſtorms, nor earthquakes, have any influence on this motion.”

This fact goes a great way towards proving the general truth of Mr. Howard’s theory, given in the Philoſophical Magazine, Vol. VII.