, is to combine with an atom consisting of
one vortex ring; then, since, for the stability of connection, the
strength of all the primaries which form the components of the compound
must be equal, the atom consisting of two links must unite with
molecules containing two atoms of the one with one link. Thus the
compound formed will be the simplest combination, consisting of one of
the atoms which consist of two vortex rings linked together with two of
the atoms consisting of only one vortex ring. Similarly, if an atom
consisting of three vortex rings linked together were to combine
directly with atoms consisting of only one vortex ring, the compound
formed would consist of the three linked atoms with three of the others,
and so on for all the combinations of atoms formed by any number of
vortex rings linked together. This suggests that the elements, called by
the chemists monads, dyads, triads and so on, consist of one, two, etc.
vortex rings linked together, for then we should know that a dyad could
not combine with less than two atoms of a monad to form a stable
compound, or a triad with less than three, and so on, which is just the
definition of the terms monad, dyad, triad."

"On looking at chemical combination from this point, we expect to find
that such compounds as Hydrochloric acid, where one atom of Hydrogen has
only to meet one atom of Chlorine; or water, where one atom of Oxygen
has only to meet two atoms or a molecule of Hydrogen, would be much more
easily and quickly formed than a compound such as ammonia gas, to form
which an atom of Nitrogen has to find itself close to three atoms of
Hydrogen at once."

"It is the case, I believe, in direct combination, that simple compounds
are formed more quickly than compound ones. We might call the ratio of
the number of links in the atom of any element, to the number in the
atom of Hydrogen, the Valency of the element. Thus the compounds H-CL,
H-I, H-F, show that the atoms of Chlorine, Iodine, Fluorine have the
same number of links as the atom of Hydrogen, so that the valency of
each of these elements is unity. From the compound H_{2}O we infer that
the atom of Oxygen consists of twice as many links as the atom of
Hydrogen. The compound H_{2}S indicates that the atoms of Sulphur have
twice as many links as the atom of Hydrogen."

"The molecules CO_{2} and Marsh Gas have each three primaries
represented by C-O-O and C-H-H respectively. According to the view we
have