raction of the body, receding from it and also from one another, with
great strength; and keeping at a distance, so as sometimes to take up a
million of times more space than they did before, in the form of a dense
body."

Newton was of opinion that matter was made up, in the last resort, of
exceedingly small solid particles, having no pores, or empty spaces
within them. Priestley, in his Disquisitions relating to Matter and
Spirit, carries the theory one step farther; and, as Newton surrounds
his exceedingly small particles with spheres of attraction and
repulsion, precluding in all cases their actual contact, Priestley is
disposed to regard the centre of these spheres as mathematical points
only. If there is no actual contact, then by the very terms no two
particles of matter were ever so near to each other, but that they
might be brought nearer, if a sufficient force could be applied for that
purpose. You had only another sphere of repulsion to conquer; and, as
there never is actual contact, the whole world is made up of one sphere
of repulsion after another, without the possibility of ever arriving at
an end.

"The principles of the Newtonian philosophy," says our author, "were no
sooner known, than it was seen how few in comparison, of the phenomena
of nature, were owing to solid matter, and how much to powers, which
were only supposed to accompany and surround the solid parts of matter.
It has been asserted, and the assertion has never been disproved, that
for any thing we know to the contrary, all the solid matter in the solar
system might be contained within a nutshell(45)."

(45) Priestley, Disquisitions, Section II. I know not by whom this
illustration was first employed. Among other authors, I find, in
Fielding (Joseph Andrews, Book II, Chap. II), a sect of philosophers
spoken of, who "can reduce all the matter of the world into a nutshell."

It is then with senses, from the impressions upon which we are impelled
to draw such false conclusions, and that present us with images
altogether unlike any thing that exists out of ourselves, that we
come to observe the phenomena of what we call the universe. The first
observation that it is here incumbent on us to make, and which we ought
to keep ever at hand, to be applied as occasion may offer, is the
well known aphorism of Socrates, that "we know only this, that we know
nothing." We have no compass to guide us through the pathless waters of
science; we h