(Footnote.  Since the above was written accounts have been received that a magazine at Fort Marlborough, containing four hundred barrels of powder, was fired by lightning and blown up on the 18th of March 1782.)

Monsoons.

The causes which produce a successive variety of seasons in the parts of the earth without the tropics, having no relation or respect to the region of the torrid zone, a different order takes place there, and the year is distinguished into two divisions, usually called the rainy and dry monsoons or seasons, from the weather peculiar to each.  In the several parts of India these monsoons are governed by various particular laws in regard to the time of their commencement, period of duration, circumstances attending their change, and direction of the prevailing wind according to the nature and situation of the lands and coasts where their influence is felt.  The farther peninsula of India, where the kingdom of Siam lies, experiences at the same time the effects of opposite seasons; the western side, in the Bay of Bengal, being exposed for half the year to continual rains, whilst on the eastern side the finest weather is enjoyed; and so on the different coasts of Indostan the monsoons exert their influence alternately; the one remaining serene and undisturbed whilst the other is agitated by storms.  Along the coast of Coromandel the change, or breaking up of the monsoon as it is called, is frequently attended with the most violent gales of wind.

On the west coast of Sumatra, southward of the equinoctial, the south-east monsoon or dry season begins about May and slackens in September:  the north-west monsoon begins about November, and the hard rains cease about March.  The monsoons for the most part commence and leave off gradually there; the months of April and May, October and November generally affording weather and winds variable and uncertain.

Cause of the monsoons.

The causes of these periodical winds have been investigated by several able naturalists, whose systems, however, do not entirely correspond either in the principles laid down or in their application to the effects known to be produced in different parts of the globe.  I shall summarily mention what appear to be the most evident, or probable at least, among the general laws, or inferences, which have been deduced from the examination of this subject.  If the sea were perfectly uninterrupted and free from the irregular influence of lands, a perpetual easterly wind would prevail in all that space comprehended between the twenty-eighth or thirteenth degrees of north and south latitude.  This is primarily occasioned by the diurnal revolution of the earth upon its axis from west to east; but whether through the operation of the sun, proceeding westward, upon the atmospheric fluid, or the rapidity of revolution of the solid body, which leaves behind it that fluid with which it is surrounded, and thereby causes it virtually