ay be done
simply by washing the surface of the board, for the water having once
got between the board and the air will run together, and the ebony will
go to the bottom; and if it does not, you have won the day.

"But methinks I hear some of my antagonists cunningly opposing this, and
telling me that they will not on any account allow their boards to be
wetted, because the weight of the water so added, by making it heavier
than it was before, draws it to the bottom, and that the addition of new
weight is contrary to our agreement, which was that the matter should be
the same.

"To this I answer, first, that nobody can suppose bodies to be put into
the water without their being wet, nor do I wish to do more to the board
than you may do to the ball. Moreover, it is not true that the board
sinks on account of the weight of the water added in the washing; for I
will put ten or twenty drops on the floating board, and so long as they
stand separate it shall not sink; but if the board be taken out and all
that water wiped off, and the whole surface bathed with one single drop,
and put it again upon the water, there is no question but it will sink,
the other water running to cover it, being no longer hindered by the
air. In the next place, it is altogether false that water can in any way
increase the weight of bodies immersed in it, for water has no weight in
water, since it does not sink. Now just as he who should say that brass
by its own nature sinks, but that when formed into the shape of a
kettle it acquires from that figure the virtue of lying in water without
sinking, would say what is false, because that is not purely brass which
then is put into the water, but a compound of brass and air; so is it
neither more nor less false that a thin plate of brass or ebony swims by
virtue of its dilated and broad figure. Also, I cannot omit to tell
my opponents that this conceit of refusing to bathe the surface of the
board might beget an opinion in a third person of a poverty of argument
on their side, especially as the conversation began about flakes of ice,
in which it would be simple to require that the surfaces should be kept
dry; not to mention that such pieces of ice, whether wet or dry, always
float, and so my antagonists say, because of their shape.

"Some may wonder that I affirm this power to be in the air of keeping
plate of brass or silver above water, as if in a certain sense I would
attribute to the air a kind of