GLOSSARY.
Accelerated Motion. Motion is said to be accelerated, when the velocity is continually increasing.
Accidental Properties. Those properties of bodies which are liable to change, as colour, form, &c.
Acute.—See [Angle].
Air. An elastic fluid. The atmosphere which surrounds the earth, is generally understood by this term, but there are many kinds of air. The term is synonymous with Gas.
Air Pump. An instrument by which vessels may be exhausted of air.
Altitude. The height in degrees of the sun, or any heavenly body, above the horizon.
Angle. The space contained between two lines inclined to each other, and which meet in a point. Angles are measured in degrees, upon a segment of a circle described by placing one leg of a pair of compasses on the angular point, and with the other, describing the segment between the two lines. If the segment be exactly 1-4th of a circle, it is called a right angle, and contains 90 deg. If more than 1-4th of a circle, it is an obtuse angle. If less, an acute angle. See [plate 2.]