Defn: An instrument for the accurate measurement of small differences of height; esp. of the differences in the height of the upper surfaces of two columns of mercury or other fluid, or of the same column at different times. It consists of a telescopic leveling apparatus (d), which slides up or down a perpendicular metallic standard very finely graduated (bb). The telescope is raised or depressed in order to sight the objects or surfaces, and the differences in vertical height are thus shown on the graduated standard. [Written also kathetometer.]
CATHETUS
Cath"e*tus, n.; pl. catheti. Etym: [L., fr. Gr. Catheter.] (Geom.)
Defn: One line or radius falling perpendicularly on another; as, the catheti of a right-angled triangle, that is, the two sides that include the right angle. Barlow.
CATHODE
Cath"ode, n. Etym: [Gr. (Physics)
Defn: The part of a voltaic battery by which the electric current leaves substances through which it passes, or the surface at which the electric current passes out of the electrolyte; the negative pole; — opposed to anode. Faraday. Cathode ray (Phys.), a kind of ray generated at the cathode in a vacuum tube, by the electrical discharge.
CATHODIC
Ca*thod"ic, a. (Physiol.)
Defn: A term applied to the centrifugal, or efferent course of the nervous infuence. Marshall Hall.
CATHODOGRAPH; CATHODEGRAPH
Ca*thod"o*graph, n. Also Ca*thod"e*graph. [Cathode + -graph.]
(Physics)
Defn: A picture produced by the Röntgen rays; a radiograph.
CAT-HOLE
Cat"-hole`, n. (Naut.)