11. The now secondary qualities of bodies would disappear, if we could discover the primary ones of their minute
parts.
Had we senses acute enough to discern the minute particles of bodies, and the real constitution on which
their sensible qualities depend, I doubt not but they would produce quite different ideas in us: and that which is
now the yellow colour of gold, would then disappear, and instead of it we should see an admirable texture of
parts, of a certain size and figure. This microscopes plainly discover to us; for what to our naked eyes produces a
certain colour, is, by thus augmenting the acuteness of our senses, discovered to be quite a different thing; and the
thus altering, as it were, the proportion of the bulk of the minute parts of a coloured object to our usual sight,
produces different ideas from what it did before. Thus, sand or pounded glass, which is opaque, and white to the
naked eye, is pellucid in a microscope; and a hair seen in this way, loses its former colour, and is, in a great
measure, pellucid, with a mixture of some bright sparkling colours, such as appear from the refraction of
diamonds, and other pellucid bodies. Blood, to the naked eye, appears all red; but by a good microscope, wherein
its lesser parts appear, shows only some few globules of red, swimming in a pellucid liquor, and how these red
globules would appear, if glasses could be found that could yet magnify them a thousand or ten thousand times
more, is uncertain.
