any others, there are the
institutions which have developed the requisite intelligence, the
printing and publishing arrangements which have spread the necessary
information, the social organisation which has rendered possible such a
complex co-operation of agencies.

Further analysis would show that the many arts thus concerned in the
economical production of a child's frock, have each of them been brought
to its present efficiency by slow steps which the other arts have aided;
and that from the beginning this reciprocity has been ever on the
increase. It needs but on the one hand to consider how utterly
impossible it is for the savage, even with ore and coal ready, to
produce so simple a thing as an iron hatchet; and then to consider, on
the other hand, that it would have been impracticable among ourselves,
even a century ago, to raise the tubes of the Britannia bridge from lack
of the hydraulic press; to at once see how mutually dependent are the
arts, and how all must advance that each may advance. Well, the sciences
are involved with each other in just the same manner. They are, in fact,
inextricably woven into the same complex web of the arts; and are only
conventionally independent of it. Originally the two were one. How to
fix the religious festivals; when to sow: how to weigh commodities; and
in what manner to measure ground; were the purely practical questions
out of which arose astronomy, mechanics, geometry. Since then there has
been a perpetual inosculation of the sciences and the arts. Science has
been supplying art with truer generalisations and more completely
quantitative previsions. Art has been supplying science with better
materials and more perfect instruments. And all along the
interdependence has been growing closer, not only between art and
science, but among the arts themselves, and among the sciences
themselves.

How completely the analogy holds throughout, becomes yet clearer when we
recognise the fact that _the sciences are arts to each other_. If, as
occurs in almost every case, the fact to be analysed by any science, has
first to be prepared--to be disentangled from disturbing facts by the
afore discovered methods of other sciences; the other sciences so used,
stand in the position of arts. If, in solving a dynamical problem, a
parallelogram is drawn, of which the sides and diagonal represent
forces, and by putting magnitudes of extension for magnitudes of force a
measurable relation is es