of the sciences as confederate and intimately interconnected
[Footnote: Roger Bacon, as we saw, had a glimpse of this
principle.]; not forming a number of isolated domains, as hitherto,
but constituting a system in which the advance of one will
contribute to the advance of the others. He exposed with masterly
ability the reciprocal relations of physics and mathematics. No man
of his day had a more comprehensive view of all the sciences, though
he made no original contributions to any. His curiosity was
universal, and as Secretary of the Academy he was obliged, according
to his own high standard of his duty, to keep abreast of all that
was being done in every branch of knowledge. That was possible then;
it would be impossible now.

In the famous series of obituary discourses which he delivered on
savants who were members of the Academy, Fontenelle probably thought
that he was contributing to the realisation of this ideal of
"solidarity," for they amounted to a chronicle of scientific
progress in every department. They are free from technicalities and
extraordinarily lucid, and they appealed not only to men of science,
but to those of the educated public who possessed some scientific
curiosity. This brings us to another important role of Fontenelle--
the role of interpreter of the world of science to the world
outside. It is closely related to our subject.

For the popularisation of science, which was to be one of the
features of the nineteenth century, was in fact a condition of the
success of the idea of Progress. That idea could not insinuate
itself into the public mind and become a living force in civilised
societies until the meaning and value of science had been generally
grasped, and the results of scientific discovery had been more or