{1} Very curious are the effects of African fever on certain minds.
Cheerfulness vanishes, and the whole mental horizon is overcast with black clouds of gloom and sadness.

The liveliest joke cannot provoke even the semblance of a smile.

The countenance is grave, the eyes suffused, and the few utterances are made in the piping voice of a wailing infant.

An irritable temper is often the first symptom of approaching fever.

At such times a man feels very much like a fool, if he does not act like one.