“The heat of the climate must necessarily be excessive; and this is augmented, in the course of the river, by high woods, without sufficient intervals, in many places, to admit of being refreshed by the winds.

“The river has, in it’s course, many noisome marshes on it’s sides; and the trees are so thick, as to intercept the rays of the sun:  consequently, the earth beneath their branches is covered with rotten leaves and putrid vegetables.  Hence arise copious collections of foul vapours, which clog the atmosphere.  These unite with large clouds, and precipitate in rains.  The rains are no sooner over, than the sun breaks forth, and shines with scorching heat.  The surface of the ground, in places not covered with trees, is scarcely dry, before the atmosphere is again loaded by another collection of clouds and exhalations, and the sun is again concealed.

“In the rainy seasons of the year, months successively pass away in this sort of vicissitudes, without the least diminution of heat; excepting at nights, when the air is poisoned by noxious chilling dews.  But, sometimes, during the periodical rains, which begin about the middle of April, and with uncertain intervals of dry weather end late in November, the torrents of water that fall, for weeks together, are prodigious, which give the river a tremendous aspect; and, from their suddenness and impetuosity, cannot be imagined, by a European, to portend any thing but a deluge.  This bursting of the waters above, and the raging of the river below, with the blackness of the nights, accompanied with horrid tempests of lightning and thunder, constitute a magnificent scene of terror unknown but in the tropic world.

“Of the little army destined for the San Juan expedition after some delay at the mouth of the river, two hundred regulars, with ammunition and stores; proceeded up the river with the Indians, in their several crafts.  It being now near the end of the dry season, the river contained very little water, and the shoals and sandy beaches rendered the passage difficult.  The men were frequently obliged to quit their boats, and unite their strength in the water, to get them through some shallow channels.  This labour continued for several days after they left the mouth of the river, till they arrived in deeper water; then, they made a quicker progress.  However, they met with many obstacles, by currents, and occasional rapids or falls; which would have been insurmountable, but for the skill of the Indians in managing the boats on those occasions.

     “On the 9th of April, this advanced party arrived at a little
     island up the river, called St. Bartholomew; which they took, after
     receiving a few shot from the enemy, by which two men were wounded.