and growing and living in this very remarkable manner in the sugary
fluid which is, so to speak, the nidus or home of the yeast.

That, in a few words, is, as far as investigation--by the help of one's
eye and by the help of the microscope--has taken us. But now there is
an observer whose methods of observation are more refined than those of
men who use their eye, even though it be aided by the microscope; a man
who sees indirectly further than we can see directly--that is, the
chemist; and the chemist took up this question, and his discovery was
not less remarkable than that of the microscopist. The chemist
discovered that the yeast plant being composed of a sort of bag, like a
bladder, inside which is a peculiar soft, semifluid material--the
chemist found that this outer bladder has the same composition as the
substance of wood, that material which is called "cellulose," and which
consists of the elements carbon and hydrogen and oxygen, without any
nitrogen. But then he also found (the first person to discover it was
an Italian chemist, named

Fabroni, in the end of the last century) that this inner matter which
was contained in the bag, which constitutes the yeast plant, was a
substance containing the elements carbon and hydrogen and oxygen and
nitrogen; that it was what Fabroni called a vegeto-animal substance,
and that it had the peculiarities of what are commonly called "animal
products."

This again was an exceedingly remarkable discovery. It lay neglected
for a time, until it was subsequently taken up by the great chemists of
modern times, and they, with their delicate methods of analysis, have
finally decided that, in all essential respects, the substance which
forms the chief part of the contents of the yeast plant is identical