ATOMIC; ATOMICAL a.
e Doctrine of definite 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…
AUTUMN n.
The third season of the year, or the season between summer and winter, often called "the fall." Astronomically, it begins in the northern temperate zone at the autumnal equinox, about September 23, and ends at the winter solstice, about December 23; but in popular language, autumn, in America, comprises September, Octo…
BACK a.
een made up. -- Back filling (Arch.), the mass of materials used in filling up the space between two walls, or between the inner and outer faces of a wall, or upon the haunches of an arch or vault. -- Back pressure. (Steam Engine) See under Pressure. -- Back rest, a guide attached to the slide rest of a lathe, and p…