folly.

And now--to end this lecture with more pleasing thoughts--What becomes of
this breath which passes from your lips? Is it merely harmful; merely
waste? God forbid! God has forbidden that anything should be merely
harmful or merely waste in this so wise and well-made world. The
carbonic acid which passes from your lips at every breath--ay, even that
which oozes from the volcano crater when the eruption is past--is a
precious boon to thousands of things of which you have daily need. Indeed
there is a sort of hint at physical truth in the old fairy tale of the
girl, from whose lips, as she spoke, fell pearls and diamonds; for the
carbonic acid of your breath may help hereafter to make the pure
carbonate of lime of a pearl, or the still purer carbon of a diamond.
Nay, it may go--in such a world of transformations do we live--to make
atoms of coal strata, which shall lie buried for ages beneath deep seas,
shall be upheaved in continents which are yet unborn, and there be burnt
for the use of a future race of men, and resolved into their original
elements. Coal, wise men tell us, is on the whole breath and sunlight;
the breath of living creatures who have lived in the vast swamps and
forests of some primaeval world, and the sunlight which transmuted that
breath into the leaves and stems of trees, magically locked up for ages
in that black stone, to become, when it is burnt at last, light and
carbonic acid, as it was at first. For though you must not breathe your
breath again, you may at least eat your breath, if you will allow the sun
to transmute it for you into vegetables; or you may enjoy its fragrance
and its colour in the shape of a lily or a rose. When you walk in a
sunlit garden, every word you speak, every breath you breathe, is feeding
the plants and flowers around. The delicate surface of the green leaves
absorbs the carbonic acid, and parts it into its elements, retaining the
carbon to make woody fibre, and courteously returning you the oxygen to