ATOMIC; ATOMICAL a.
efinite proportions (Chem.), teaches that chemical combinations take place between the supposed ultimate particles or atoms of bodies, in some simple ratio, as of one to one, two to three, or some other, always expressible in whole numbers. -- Atomic weight (Chem.), the weight of the atom of an element as compared wit…
AURORA n.
rly called northern lights. A luminous meteoric phenomenon, visible only at night, and supposed to be of electrical origin. This species of light usually appears in streams, ascending toward the zenith from a dusky line or bank, a few degrees above the northern horizon; when reaching south beyond the zenith, it forms w…