When the troops were in Zealand, where the poison was in a high degree of concentration, they had not been a fortnight in the cantonments, before several of the men belonging to those regiments which were stationed nearest the inundations, were seized simultaneously with lassitude and inquietude, a sensation of burning heat, intense thirst, frequent nausea, sickness and vomiting, aching of the bones, pain in the back, and violent headache. There were some instances of the head being so suddenly and violently affected that, without any previous complaint, the men ran about in a wild manner, and were believed to be mad, till the solution of the fit by a sweat, and its periodic return, discovered the true nature of their delirium. Most of the men were first taken ill upon their return from forage. The regiment being cantoned close upon the inundations, and many of the quarters being above two leagues from the place where the magazines were kept, the men were obliged to set out about four in the morning, in order to get back before the greatest heat of the day. At this early hour, the meadows and marshes on each side of the road were covered with a thick fog, of an offensive smell. The party generally returned before noon; but several of the men, even before they could get back to their quarters, were already in a violent fever; some, in this short space of time, were actually delirious; and a few, on their way home, were so suddenly taken with a phrenzy, as to throw themselves from their trusses into the water, imagining they were to swim to their quarters. One man, on reaching home, was suddenly seized with intense headache, got out of his quarters, and ran about the fields like one distracted. Three years after this sickness, it was found that two of the men who were thus suddenly affected with phrenzy, though they recovered of their fever, had ever since been epileptic, and that all the rest who had been ill, remained exceedingly liable to returns of an intermitting fever. The suddenness with which fever sometimes attacks individuals on board a ship, or even an entire ship’s crew, on the approach of the vessel to a shore where this poison is generated in large quantity, and in a high state of concentration, illustrates its operation, perhaps, in a still more striking manner. Dr. Maculloch, who has laboured with great ability and zeal to recal attention to the most important and long-forgotten subject of malaria, relates an instance of some men on board a ship, who were seized, while the vessel was five miles from shore with fatal cholera, the very instant the land-smell first became perceptible. Several of these men, who were unavoidably employed on deck, died of the disease in a few hours. The armourer of the ship, who, before he could protect himself from the noxious blast, was accidentally delayed on deck a few minutes, to clear an obstruction in the chain cable, was seized with the malady while in that act, and was dead in a few hours.