ns an ineffaceable characteristic of the species, ever
ready to declare itself should circumstances demand it. The generations
of to-day are as much endowed with it as the generations of yore;
without apprenticeship, without the example of others, they have within
themselves, in the potential state, the industrial aptitude of their
ancestors. If aroused by the stimulus of necessity, this aptitude will
pass suddenly from inaction to action. When, therefore, the Sparrow
still from time to time indulges in spherical building, this is not
progress on his part, as is sometimes contended; it is, on the contrary,
a retrogression, a return to the ancient customs, so prodigal of labour.
He is behaving like the Osmia who, in default of a reed, makes shift
with a Snail-shell, which is more difficult to utilize but easier to
find. The cylinder and the hole in the wall stand for progress; the
spiral of the Snail-shell and the ball-shaped nest represent the
starting-point.

I have, I think, sufficiently illustrated the inference which is borne
out by the whole mass of analogous facts. Animal industry manifests a
tendency to achieve the essential with a minimum of expenditure; after
its own fashion, the insect bears witness to the economy of energy. On
the one hand, instinct imposes upon it a craft that is unchangeable
in its fundamental features; on the other hand, it is left a certain
latitude in the details, so as to take advantage of favourable
circumstances and attain the object aimed at with the least possible
expenditure of time, materials and work, the three elements of
mechanical labour. The problem in higher geometry solved by the Hive-bee
is only a particular case--true, a magnificent case,--of this general
law of economy which seems to govern the whole animal world. The wax
cells, with their maximum capacity as against a minimum wall-space, are
the equivalent, with the superaddition of a marvellous scientific skill,
of the Osmia's compartments in which the stonework is reduced to a
minimum through the selection of a reed. The artificer in mud and the
artificer in wax obey the same tendency: they economize. Do they know
what they are doing? Who would venture to suggest it in the case of
the Bee grappling with her transcendental problem? The others,
pursuing their rustic art, are no wiser. With all of them, there is no
calculation, no premeditation, but simply blind obedience to the law of
general harmony.

CHAPTER 8