Thus an atom of oxygen would contain sixteen times as many corpuscules as would an atom of hydrogen, weighing only one-sixteenth as much. This means that thirty-four thousand millions of millions of atoms of hydrogen would weigh in the aggregate one gram. These calculations are based on determination of the electric charge of corpuscules. Corpuscles are calculated as being one-thousandth of the mass of an atom of hydrogen. When atoms unite to form molecules, they are said to saturate each other.
Elements vary in the saturating power of their atoms.
The saturating power is called atomicity or valency. Some elements have a valency of one, and are termed monads. A monad can saturate a monad. Others are termed dyads, have a valency of two, two monads being required to saturate one dyad, while one dyad can saturate another dyad. Valencies run on through triads, tetrads, pentads, hexads, heptads, and octads, designating valencies of three, four, five, six, seven, and eight respectively.