asure of Bacon's own
advancement as an interpreter of Nature. It was a posthumous work, and
the editor, his secretary, tells us that he often said that if he had
considered his reputation he would have withheld it from the world,
because it was not digested according to his own method: yet he
persuaded himself that the causes therein assigned were far more
certain than those rendered by others, "not for any excellence of his
own wit, but in respect of his continual conversation with Nature and
Experience," and mankind might stay upon them till true Axioms were
more fully discovered. When, however, we examine the causes assigned,
we find that in practice Bacon could not carry out his own precepts:
that he did not attempt to creep up to an explanation by slow and
patient ascent, but jumped to the highest generalisations: and that
his explanatory notions were taken not from nature, but from the
ordinary traditions of mediaeval physical science. He deceived himself,
in short, in thinking that he could throw aside tradition and start
afresh from observation.

For example. He is struck by the phenomenon of bubbles on water: "It
seemeth somewhat strange that the air should rise so swiftly, while it
is in the water, and when it cometh to the top should be stayed by so
weak a cover as that of the bubble is". The swift ascent of the air he
explains as a "motion of percussion," the water descending and forcing
up the air, and not a "motion of levity" in the air itself. "The cause
of the enclosure of the bubble is for that the appetite to resist
separation or discontinuance, which is strong in solids, is also
in liquors, though fainter and weaker." "The same reason is of the
roundness of the bubble, as well for the skin of water as for the air
within. For the air likewise avoideth discontinuance, and therefore
casteth itself into a round figure. And for the stop and arrest of the
air a little while, it showeth that the air of itself hath little or
no appetite of ascending."[3] These notions were not taken direct from
the facts: they descended from Aristotle. He differs from Aristotle,
however, in his explanation of the colours of birds' feathers.
"Aristotle giveth the cause vainly" that birds are more in the beams
of the sun than beasts. "But that is manifestly untrue; for cattle are
more in the sun than birds, that live commonly in the woods or in some
covert. The true cause is that the excrementitious moisture of living
creature