to the lower country; but they differed respecting the frequency of
these visits. The animal probably regulates them according to the
nature of the food on which it has lived. It is, however, certain,
that tortoises can subsist even on these islands where there is no
other water than what falls during a few rainy days in the year.
I believe it is well ascertained, that the bladder of the frog acts as
a reservoir for the moisture necessary to its existence: such seems to
be the case with the tortoise. For some time after a visit to the
springs, their urinary bladders are distended with fluid, which is said
gradually to decrease in volume, and to become less pure. The
inhabitants, when walking in the lower district, and overcome with
thirst, often take advantage of this circumstance, and drink the
contents of the bladder if full: in one I saw killed, the fluid was
quite limpid, and had only a very slightly bitter taste. The
inhabitants, however, always first drink the water in the pericardium,
which is described as being best.
The tortoises, when purposely moving towards any point, travel by night
and day, and arrive at their journey's end much sooner than would be
expected. The inhabitants, from observing marked individuals, consider
that they travel a distance of about eight miles in two or three days.
One large tortoise, which I watched, walked at the rate of sixty yards
in ten minutes, that is 360 yards in the hour, or four miles a
day,--allowing a little time for it to eat on the road. During the
breeding season, when the male and female are together, the male utters
a hoarse roar or bellowing, which, it is said, can be heard at the
distance of more than a hundred yards. The female never uses her voice,
and the male only at these times; so that when the people hear this
noise, they know that the two are together. They were at this time
(October) laying their eggs. The female, where the soil is sandy,
deposits them together, and covers them up with sand; but where the
ground is rocky she drops them indiscriminately in any hole: Mr. Bynoe
found seven placed in a fissure. The egg is white and spherical; one
which I measured was seven inches and three-eighths in circumference,
and therefore larger than a hen's egg. The young tortoises, as soon as
they are hatched, fall a prey in great numbers to the carrion-feeding
buzzard. The old ones seem generally to die from accidents, as from
falling down precipices: at least, several of the inhabitants told me,
that they never found one dead without some evident cause.
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