The Gulf of Guinea has in its own bosom a system of hurricanes and squalls, of which little is known but their existence and their danger. A description of them, of rather an old date, specifies as a fact that they begin by the appearance of a small mass of clouds in the zenith, which widens and extends till the canopy covers the horizon. Now if this were true of any given spot, it would indicate that the hurricane always began there. The appearance of a patch of cloud in the zenith could be true of only one place out of all those which the hurricane influenced. If it is meant that _wherever_ the phenomenon originated, _there_ a mass of cloud gradually formed in the zenith, this would be a most important particular in regard to the proximate cause of the phenomenon, for it would mark a rapid direction upwards of the atmosphere at that spot as the first observable incident of the series. That the movements produced would subsequently become whirling or circumvolant, is a mechanical necessity. But the force of the movement ought not to be strongest at the place where the mischief had its origin. The squalls, with high towering clouds, which rise like a wall on the horizon, involve the same principles as to the formation of the vapor, and are easily explicable. They are not necessarily connected with circular hurricanes; but the principles of their formation may modify the intensity of the blasts in a circumvolant tornado. Since in the Gulf of Guinea they come from the eastward, it is to be inferred that they are ripples or undulations in an air current. In regard to all of this, it is necessary to speak doubtfully, for there is a great lack of accurate and detailed observation on these points. Its position and physical characteristics give to this continent great influence over the rest of the earth. Africa, America, and Australia have nearly similar relations to the great oceans interposed respectively between them. Against the eastern sides of these regions are carried from the ocean those strange, furious whirlings in the shallow film of the earth’s atmosphere, which constitute hurricanes. It is evident that these oceans are mainly the channels in which the surface winds move, which are drawn from colder regions towards the equator. The shores are the banks of these air streams. The return currents above flow over every thing. They are thus prevalent in the interior, so that the climatic conditions there are different from those on the seaboard. These circumstances in the southern extra-tropical regions are accompanied by corresponding differences in the character of the vegetable world.