PHŒNIXVILLE                                        14

gion with good farm-land in the valleys, in which are extensive olive-groves, and controls a large trade in live-stock, grain, hay, honey, wines, oranges and other fruits. The chief industrial interests are the stockyards, machine-shops and jobbing houses. Among the public buildings are the capitol, agricultural experiment-station, insane asylum, court-house, city-hall, churches and schools. It is provided with good schools, both public and private. An Indian school here deserves special mention. It has more than 400 students, and, besides its regular course of instruction, has departments that teach manual training. Government is vested in a mayor, who holds office for two years, and a council. Population 11.134-

Phcenixville, Pa., a borough in Chester County, at the confluence of Schuylkill River and French Creek, 23 miles from Philadelphia. It manufactures silk, cotton goods, hosiery and matches, but of greatest importance is its iron industry. It contains rolling-mills, blast-furnaces, bridge-works and iron-mills, including one of the largest plants in the country. Phcenixville has good schools, a public library, a park and a hospital. The waterworks are owned and operated by the borough, and it has the service of two railroads. Population 10,743-

Phonet'ics, the science of the sounds of the human voice. Sound is produced by the expulsion of air from the lungs through the windpipe. When this air in its passage through the throat sets the vocal cords in vibration, voice is produced. After passing through the throat the voice enters the mouth or nose or both. As a practical science, phonetics comprehends not only a knowledge of the sounds uttered in human speech, but the invention or discovery of an alphabetical symbol to represent each. The sounds are of two kinds ! Fixed sounds, where the cavities of the mouth remain unchanged during the passage of the air; and glides, where these cavities are constantly changing or, in other words, where the utterance is variously modified by the tongue, palate, lips and teeth. The former sounds are called vowels, and in English are represented by the letters, a, e, i, o, u, y; the latter sounds are called consonants, that is, with-sounders, as they are sounded with the vowels, but not alone. The great variations in spelling and pronouncing English have long been a source of perplexity to foreigners learning our language, and have caused many "phonetic reformers" to arise, with plans for producing uniformity; but none of these has ever been adopted, except in the case of a few words. Perhaps the reason of this is that, however "irregular" may be the spelling of so many words, yet the forms in which they are written have become as firmly fixed in our mental habit

^                                           PHONOMETER

as are the sounds they represent and the ideas conveyed by those sounds; hence we can never consent to any changes, except those that are gradual and proceed as by a growth. Another difficulty in the phonetic reform would be that, even if it were possible to devise a fixed alphabetical symbol for every sound or combination of sounds, to which all good writers would conform, the pronunciation of words would at once begin to vary and in time our spelling and pronunciation might be as "irregular" as now.

Pho'nograph, an instrument invented by Edison in 1877 for recording and reproducing words spoken by the human voice. Leon Scott had already shown that, by speaking in front of a diaphragm, on the rear side of which was fixed a stylus, he could obtain a graphical record of the human voice on a cylinder rotating behind the diaphragm. The step which Edison made was to introduce a wax cylinder and a needlepoint attached to the diaphragm. On rotating the wax cylinder, the needle-point cuts a groove. If, while this groove is being cut, one "talks to the diaphragm" the indentations of the needle-point in the wax will vary with each pulsation of the voice. The axis of the cylinder is so provided with a screw that the groove takes the form of a spiral as the cylinder is rotated and translated while the stylus is fixed in one position. A record having been impressed upon the wax, it is only necessary to allow the stylus again to trace the groove in order to impress upon the diaphragm exactly — or nearly exactly — the same vibrations which originally produced the groove. In this way the phonograph is made to repeat whatever is said to it. A new phonographic principle was in 1900 invented by Poulsen, a Danish engineer. Poulsen uses the current in a telephone circuit to magnetize a strip of steel tape which is drawn continuously between the poles of an electromagnet, the electromagnet being energized by the telephone current. The record of anything spoken into the telephone is stored in the magnetization of the steel tape. Accordingly when the steel tape is again drawn between the poles of the electromagnet, the telephone in the circuit will, owing to currents induced by the steel tape, repeat whatever was originally spoken to it. Still a third phonographic principle was in 1901 devised by Nernst; but has not been perfected. It is based upon the electrolysis produced by an electric current.

Phonog'raphy. See Shorthand.

Phonom'eter is an instrument of Edison's invention for testing the force of the human voice in speaking. It consists chiefly of a mouthpiece and diaphragm, behind the latter of which is placed a delicate mechanism which operates a 15-inch fly-wheel by means of which a hole can be bored in an ordinary pine board.