The speech, or more probably our bad manners, made some impression on our guide, for he declined, although offered double pay, to go any further.
A great deal of fever comes in with March and April; in March, if considerable intervals take place between the rainy days, and in April always, for then large surfaces of mud and decaying vegetation are exposed to the hot sun.

In general an attack does not continue long, but it pulls one down quickly; though when the fever is checked the strength is as quickly restored.

It had long been observed that those who were stationed for any length of time in one spot, and lived sedentary lives, suffered more from fever than others who moved about and had both mind and body occupied; but we could not all go in the small vessel when she made her trips, during which the change of place and scenery proved so conducive to health; and some of us were obliged to remain in charge of the expedition's property, making occasional branch trips to examine objects of interest in the vicinity.

Whatever may be the cause of the fever, we observed that all were often affected at the same time, as if from malaria.

This was particularly the case during a north wind: it was at first commonly believed that a daily dose of quinine would prevent the attack.