Page:Collier's New Encyclopedia v. 07.djvu/296

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FHOLAS 230 PHOSGENE also has manufactories of copper and cot- ton goods. The assessed valuation is $3,500,000. Pop. (1910) 10,734; (1920) 10,484. PHOLAS, piddock; the typical genus of the Pholadidse. Shell long, cylindri- cal, accessory valves protecting the dorsal margin. Animal with a large, truncated foot, body with a fan-like termination. They live in symmetrical vertical burrows. Recent species 32, from most seas: fossil 25, from the Up- per Lias onward. PHONETIC, or PHONETICAL, rep- resenting sound; pertaining to the repre- sentation of sounds; a term applied to alphabetic or literal characters which represent sounds, as a, b, c; as opposed to ideographic, which represent objects or symbolize abstract ideas, as in Egyp- tian hieroglyphics. Phonetic spelling, a system of spelling in which the words are spelled exactly as they are pronounced, the sounds being represented by charac- ters each of which represents a single sound. Phonetic printing was first sug- gested by Isaac Pitman, of Bath, Eng- land, and reduced to a system by him in conjunction with A. J. Ellis, in the years 1843-1846. Since that time many systems of phonetic spelling have been proposed and several are used by stenog- raphers in the United States. PHONOGRAPH, an instrument for recording and reproducing sound. The instrument in its present stage of per- fection has been evolved through, ex- tended laboratory work from the first principles that were demonstrated by a device invented in 1855 by Leon Scott. In Scott's instrument sound was collected by an ellipsoidal receiver, which was open at one end. A small tube was fastened to the other end of the receiver and a tightly stretched membrane to which a bristle was attached was fastened to the end of the tube. In front of the bristle was a cylinder surfaced with material sufficiently soft to take impressions from the bristle as the sound waves collected in the receiver caused the membrane to move the bristle; and at the same time the cylinder was made to move so that a record of the vibrations was made upon the soft surface of the cylinder. In 1877 Charles Crass placed before the French Academy of Sciences a method of reproducing the fragile first cylinder by photoengraving on some harder surface and Konig of Paris made many changes and improvements on Scott's first machine. Because of the great possibilities sug- gested by the early laboratory models Thomas A. Edison started an intensive study of this field about 1877 and the real life of the phonograph began, al- though his efforts were not concentrated in this field until a later date, and the machine to-day is a result of constant laboratory experimentation and improve- ment. Other names that should be mentioned in the development of the instrument are Bell and Tainter, who in 1885 invented the gramophone or machine which used a wax cylinder and a horizontal groove, and Emil Berliner who introduced the disk record in which the record of vibra- tions was made in the horizontal in place of the vertical plane. The modern machine consists essenti- ally of a reproducer in which a metal stylus or jeweled point transmits the vibrations to some tightly stretched sur- face; the vibrations are carried through an arm to a tone chamber. The record is revolved by a turntable which is ac- cuated either by clockwork or an electric motor. The fact that the early records, which were made of a composition which had wax as its principal ingn^edient, were fragile and would not wear well, led to experiments which would produce a more durable material. A method in which the original record is electro-plated with gold and re-enforced with a less valuable material and used as a die which stamps the records into a plastic material which is afterward hardened is now used. Almost every musical artist of note is under contract by one of the companies manufacturing phonograph records, and the industry of making phonographs and records has grown to tremendous size; many thousands of people are employed in the making, and a vast staff of research workers are engaged in mak- ing studies which tend toward the im- provement of the product. See Gramo- phone. PHONOGRAPHY, a descriptidh of the sounds uttered by the organs of speech. Also the representation of sounds by cer- tain characters, each of which represents one sound, and always the same sound. Its special application is to alphabetical writing, in which sounds or articulations are represented by signs or letters, as opposed to the system in which the rep- resentation is by ideas, symbols, or cipher. Specifically, a method of writ- ing, or graphically representing lan- guage, invented by Isaac Pitman, of Bath, England. See Shorthand. Also the art of using, or registering by means of, the phonograph; the construction of phonographs. PHOSGENE, carbon oxychloride, car- bonyl chloride, chlorocarbonic acid, C