a sermon to which Bossuet might have given his approbation, while
another may hear a discourse in which Socrates would find nothing new.

But great as these changes may be, they sink into insignificance beside
the progress of physical science, whether we consider the improvement
of methods of investigation, or the increase in bulk of solid
knowledge. Consider that the labours of Laplace, of Young, of Davy, and
of Faraday; of Cuvier, of Lamarck, and of Robert Brown; of Von Baer,
and of Schwann; of Smith and of Hutton, have all been carried on since
Priestley discovered oxygen; and consider that they are now things of
the past, concealed by the industry of those who have built upon them,
as the first founders of a coral reef are hidden beneath the life's
work of their successors; consider that the methods of physical science
are slowly spreading into all investigations, and that proofs as valid
as those required by her canons of investigation are being demanded of
all doctrines which ask for men's assent; and you will have a faint
image of the astounding difference in this respect between the
nineteenth century and the eighteenth.

If we ask what is the deeper meaning of all these vast changes, I think
there can be but one reply. They mean that reason has asserted and
exercised her primacy over all provinces of human activity: that
ecclesiastical authority has been relegated to its proper place; that
the good of the governed has been finally recognised as the end of
government, and the complete responsibility of governors to the people
as its means; and that the dependence of natural phenomena in general
on the laws of action of what we call matter has become an axiom.

But it was to bring these things about, and to enforce the recognition
of these truths, that Joseph Priestley laboured. If the nineteenth