Part 248

{ Pho`to*log"ic (?), Pho`to*log"ic*al (?), } a. Pertaining to photology, or the doctrine of light.

Pho*tol"o*gist (?), n. One who studies or expounds the laws of light.

Pho*tol"o*gy (?), n. [Photo- + -logy: cf. F. photologie.] The doctrine or science of light, explaining its nature and phenomena; optics.

Pho`to*mag*net"ic (?), a. Of or pertaining to photomagnetism.

Pho`to*mag"net*ism (?), n. The branch of science which treats of the relation of magnetism to light.

Pho`to*me*chan"ic*al (?), a. Pertaining to, or designating, any photographic process in which a printing surface is obtained without the intervention of hand engraving.

Pho*tom"e*ter (?), n. [Photo- + -meter: cf. F. photomËtre.] (Physics) An instrument for measuring the intensity of light, or, more especially, for comparing the relative intensities of different lights, or their relative illuminating power.

{ Pho`to*met"ric (?), Pho`to*met"ric*al (?), } a. [Cf. F. photomÈtrique.] Of or pertaining to photometry, or to a photometer.

Pho*tom`e*tri"cian (?), n. One engaged in the scientific measurement of light.

Pho*tom"e*try (?), n. [Cf. F. photomÈtrie.] That branch of science which treats of the measurement of the intensity of light.

Pho`to*mi"cro*graph (f`t*m"kr*grf), n. [Photo- + micro + -graph.] 1. An enlarged or macroscopic photograph of a microscopic object. See Microphotograph.

2. A microscopically small photograph of an object.

Pho`to*mi*crog"ra*phy (?), n. The art of producing photomicrographs.

Pho`to*pho"bi*a (?), n. [NL., fr. Gr. fw^s, fwto`s, light + &?; fear.] (Med.) A dread or intolerance of light. Sir T. Watson.

Pho"to*phone (?), n. [Photo- + Gr. &?; sound.] (Physics) An apparatus for the production of sound by the action of rays of light. A. G. Bell.

Pho`to*phon"ic (?), a. Of or pertaining to photophone.

Pho*toph"o*ny (?), n. The art or practice of using the photophone.

Pho*top"si*a (?), n. [NL., fr. Gr. fw^s, fwto`s, light + &?; sight.] (Med.) An affection of the eye, in which the patient perceives luminous rays, flashes, coruscations, etc. See phosphene.

Pho*top"sy (?), n. Same as Photopsia.

Pho`to*re*lief" (?), n. A printing surface in relief, obtained by photographic means and subsequent manipulations. Knight.

Pho"to*scope (?), n. [Photo- + -scope.] (Physics) Anything employed for the observation of light or luminous effects.

Pho`to*scop"ic (?), a. Of or pertaining to the photoscope or its uses.

Pho`to*sculp"ture (?), n. [Photo- + sculpture.] A process in which, by means of a number of photographs simultaneously taken from different points of view on the same level, rough models of the figure or bust of a person or animal may be made with great expedition.

Pho"to*sphere (?), n. [Photo- + sphere.] A sphere of light; esp., the luminous envelope of the sun.

Pho`to*spher"ic (?), a. Of or pertaining to the photosphere.

Pho*tot"o*nus (?), n. [NL. See Photo- , and Tone.] (Bot.) A motile condition in plants resulting from exposure to light. -- Pho`to*ton"ic (#), a.

Pho`to*trop"ic (?), a. [Photo- + Gr. &?; to turn.] (Bot.) Same as Heliotropic.

Pho"to*type (?), n. [Photo- + -type.] A plate or block with a printing surface (usually in relief) obtained from a photograph; also, any one of the many methods of processes by which such a printing surface is obtained.