First, however, I must notice one fact as to this transportation from Holland, partly because it is a necessary fact in the history of malaria, and partly because it might be used as an argument against the view which I have just given. The east winds of autumn are not supposed to bring remittents, as those of spring bring agues, though I cannot assert that this is absolutely true. Being assumed, the solution is easy. If the winds of this nature in spring, are notedly moist, and thus vehicles of malaria, the case is exactly the reverse with the east winds of summer and autumn; or as the east wind may be the most moist of winds, so may it be the most dry; while it is a consequence of its extreme dryness, in fact, that it is always the very cause of our burning summers. This is the history of our last summers, and it is invariable, whether as it relates to seasons or single days; and it is plainly owing to its permitting the more ready transmission of the sun’s rays. That it is the very harmattan of Africa, it is almost unnecessary to say; and as dry wind is not a conductor of malaria, as that poison is in fact decomposed or destroyed in these circumstances, daily and invariably, it is easy to see why the remittents of Holland should not be transported, like its intermittents, though even this may possibly happen under particular circumstances. To proceed; and to the next remarkable facts connected with the propagation of malaria.—The most singular of these is its limitation, or that yet unexplained property by which it is [p050] determined in a particular direction, or confined to a particular spot, while it is a piece of knowledge of some practical value. There is an appearance of incredibility about many of these facts, and, accordingly, they have not only been disbelieved but ridiculed, although nothing in the whole history of this substance is better established. With respect to direction, in the first place, it is remarked in Italy, currently, that this poison will enter the lower stories of houses, particularly with open windows, when the next above escape; and hence, in many places, no one ventures to sleep on ground floors: and the truth of this was confirmed in the barracks at Jamaica by Dr. Hunter; as the cases of fever occurring among the men in the lower rooms much exceeded those which happened in the upper ones. But I am also informed, that in some places in Norfolk this peculiarity is reversed; or that there are houses where it is remarked that the ground-floors are safe, while no one can sleep in the upper stories without hazard.