figure of the same walnut-tree, will return to float, as
unquestionably we shall, then I must desire my opponents to
forbear to attribute the floating of the ebony to the figure of
the board, since the resistance of the water is the same in
rising as in sinking, and the force of ascension of the
walnut-tree is less than the ebony's force for going to the
bottom.

"Now let us return to the thin plate of gold or silver, or the
thin board of ebony, and let us lay it lightly upon the water, so
that it may stay there without sinking, and carefully observe the
effect. It will appear clearly that the plates are a considerable
matter lower than the surface of the water, which rises up and
makes a kind of rampart round them on every side. But if it has
already penetrated and overcome the continuity of the water, and
is of its own nature heavier than the water, why does it not
continue to sink, but stop and suspend itself in that little
dimple that its weight has made in the water? My answer is,
because in sinking till its surface is below the water, which
rises up in a bank round it, it draws after and carries along
with it the air above it, so that that which, in this case,
descends in the water is not only the board of ebony or the plate
of iron, but a compound of ebony and air, from which composition
results a solid no longer specifically heavier than the water, as
was the ebony or gold alone. But, gentlemen, we want the same
matter; you are to alter nothing but the shape, and, therefore,
have the goodness to remove this air, which may 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.