ASTATIC a.
Having little or no tendency to take a fixed or definite position or direction: thus, a suspended magnetic needle, when rendered astatic, loses its polarity, or tendency to point in a given direction. Astatic pair (Magnetism), a pair of magnetic needles so mounted as to be nearly or quite astatic, as in some galvanomet…
ATHWART prep. 2 definitions
Across the direction or course of; as, a fleet standing athwart our course. Athwart hawse, across the stem of another vessel, whether in contact or at a small distance. -- Athwart ships, across the ship from side to side, or in that direction; -- opposed to fore and aft.
ATMOSPHERIC; ATMOSPHERICAL a.
ic pressure, the pressure exerted by the atmosphere, not merely downwards, but in every direction. In amounts to about 14.7 Ibs. on each square inch. -- Atmospheric railway, one in which pneumatic power, obtained from compressed air or the creation of a vacuum, is the propelling force. -- Atmospheric tides. See under…
AXIS n.
posite sides. -- Synclinal axis, a line from which the strata slope upward in opposite directions, so as to form a valley. -- Axis cylinder (Anat.), the neuraxis or essential, central substance of a nerve fiber; -- called also axis band, axial fiber, and cylinder axis. -- Axis in peritrochio, the wheel and axle, one…
BALL n.
joint, a joint in which a ball moves within a socket, so as to admit of motion in every direction within certain limits. -- Ball bearings, a mechanical device for lessening the friction of axle bearings by means of small loose metal balls. -- Ball cartridge, a cartridge containing a ball, as distinguished from a blan…