During the prevalence of the cholera at Mauritius these birds
disappeared. Such a circumstance had never before occurred, and
the real cause of their departure is still a mystery.
May it not have been, that some species of insect upon which they
fed had likewise migrated, and that certain noxious animalcules,
which had been kept down by this class, had thus multiplied
within the atmosphere until their numbers caused disease? All
suppositions on such a subject must, however, remain in
obscurity, as no proof can be adduced of their correctness. The
time may arrive when science may successfully grapple with all
human ailments, but hitherto that king of pestilence, the
"cholera," has reduced the highest medical skill to miserable
uncertainty.
Upon reconsidering the dangers of fevers, dysentery, etc., in the
swampy and confined districts described, the naturalist may
become somewhat less ardent in following his favorite pursuit.
Of one fact I can assure him that no matter how great the natural
strength of his constitution, the repeated exposure to the
intense heat of the sun, the unhealthy districts that he will
visit, the nights redolent of malaria, and the horrible water
that he must occasionally drink, will gradually undermine the
power of the strongest man.
Pages:
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243