certainty of the Particulars that we admit: This is the first rise whereon
truth is to begin, and here the most severe, and most impartial diligence,
must be imployed; the storing up of all, without any regard to evidence or
use, will only tend to darkness and confusion. We must not therefore esteem
the riches of our Philosophical treasure by the _number_ only, but chiefly
by the _weight_; the most _vulgar_ Instances are not to be neglected, but
above all, the most _instructive_ are to be entertain'd; the footsteps of
Nature are to be trac'd, not only in her _ordinary course_, but when she
seems to be put to her shifts, to make many _doublings_ and _turnings_, and
to use some kind of art in indeavouring to avoid our discovery.

The next care to be taken, in respect of the Senses, is a supplying of
their infirmities with _Instruments_, and, as it were, the adding of
_artificial Organs_ to the _natural_; this in one of them has been of late
years accomplisht with prodigious benefit to all sorts of useful knowledge,
by the invention of Optical Glasses. By the means of _Telescopes_, there is
nothing so _far distant_ but may be represented to our view; and by the
help of _Microscopes_, there is nothing so _small_, as to escape our
inquiry; hence there is a new visible World discovered to the
understanding. By this means the Heavens are open'd, and a vast number of
new Stars, and new Motions, and new Productions appear in them, to which
all the ancient Astronomers were utterly Strangers. By this the Earth it
self, which lyes so neer us, under our feet, shews quite a new thing to us,
and in every _little particle_ of its matter; we now behold almost as great
a variety of Creatures, as we were able before to reckon up in the whole
_Universe_ it self.

It seems not improbable, but that by these helps the subtilty of the
composition of Bodies, the structure of their parts, the various texture of
their matter, the instruments and manner of their inward motions, and all