spring from
them, balance themselves, as though, upon a see-saw, which has a certain
play, but never so much as that equilibrium should be altogether lost.
As everything in the universe is in movement, and as all the forces
which are contained in matter act one against the other and
counterbalance one another, all is done by a kind of oscillation; of
which the mean points are those to which we refer as being the ordinary
course of nature, while the extremes are the periods which deviate from
that course most widely. And, as a matter of fact, with animals as much
as with plants, a time of unusual fecundity is commonly followed by one
of sterility; abundance and dearth come alternately, and often at such
short intervals that we may foretell the production of a coming year by
our knowledge of the past one. Our apples, pears, oaks, beeches, and the
greater number of our fruit and forest trees, bear freely but about one
year in two. Caterpillars, cockchafers, woodlice, which in one year may
multiply with great abundance, will appear but sparsely in the next.
What indeed would become of all the good things of the earth, what would
become of the useful animals, and indeed of man himself, if each
individual in these years of excess was to leave its quotum of
offspring? This, however, does not happen, for destruction and sterility
follow closely upon excessive fecundity, and, independently of the
contagion which follows inevitably upon overcrowding, each species has
its own special sources of death and destruction, which are of
themselves sufficient to compensate for excess in any past generation.

"Nevertheless the foregoing should not be taken in an absolute sense,
nor yet too strictly,--especially in the case of those races which are
not left entirely to the care of Nature. Those which man takes care
of--commencing with his own--are more abundant than they would be
without his care, yet, as his power of taking this care is limited, the
increase which has taken place is also fixed, and has long been
restrained within impassable boundaries. Again, though in civilized
countries man, and all the animals useful to him, are more numerous than
in other places, yet their numbers never become excessive, for the same
power which brings them into being destroys them as soon as they are
found inconvenient."[90]

_The Carnivora--Sensation._

Buffon begins his seventh volume with some remarks on the _carnivora_ in
general, which I wo