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Rh poor, all tend to broaden their first elements. That of (eə) is the low-front-narrow vowel. The other two begin with lowered forms of the wide (i) and (u) respectively. In (uə) the lowering is often carried so far as to make poor almost, or completely, into pore (pɔə).

The following arrangement of the English consonants will show their organic relations to one another.

The “aspirate” (h) may be regarded either as a throat-consonant or as a breath-glide.

Characteristic features of the English consonant-system are the large number of hisses and buzzes, the sharp distinction of breath and voice, and, negatively, the absence of the open-back consonants, and of the voiceless forms of the vowel-like consonants (l, r) and the nasals, most of which still existed in Old English.

.—The most important general works are: H. Sweet, A Primer of Phonetics (3rd ed, Ox ord, 1906); E. Sievers, Grundzüge der Lautphysiologie (5th ed., Leipzig, 1901); W. Vietor, Elemente der Phonetik des Deutschen, Englischen und Französischen (5th ed, Leipzig, 1904); O. Jesperson, Lehrbuch der Phonetik (Leipzig, 1904); M. Trautmann, Die Sprachlaute (Leipzig, 1884–1886); Le Maître Phonétique, organe de l'association phonétique internationale (apply to Dr P. Passy, Bourg-la-Reine, France). For the laws of sound-change, see the above-mentioned work of Sievers; H. Sweet, A History of English Sounds (Oxford, 1888); P. Passy, Les Changements phonetiques (Paris, 1890). For phonetics in language-teaching see H. Sweet, The Practical Study of Languages (London, 1899); O. Jesperson, How to Learn a Foreign Language (London, 1904). For phonetic shorthand, H. Sweet, A Manual of Current Shorthand (Oxford, 1892). For the application of phonetics and phonetic notation to the practical study of special languages, H. Sweet, A Primer of Spoken English (2nd ed., Ox ord, 1895); F. Beyer and P. Passy, Elementarbuch des gesprochenen Französisch (2nd ed, Cothen, 1905); W. Vietor, Deutsches Lesebuch in Lautschrift (Leipzig, 1899).

 PHONOGRAPH (Gr., sound, , to write), an instrument for imprinting the vibrations of sound on a moving surface of tinfoil or wax in such a form that the original sounds can be faithfully reproduced by suitable mechanism. Many attempts had been made by earlier experimenters to obtain tracings of the vibrations of bodies emitting sound, such as tuning-forks, membranes, and glass or metallic disks. In 1807 Thomas Young (Lectures, i. 191) described a method of recording the vibrations of a tuning-fork on the surface of a drum; his method was fully carried out by Wilhelm Wertheim in 1842 (Recherches sur l'élasticité, 1$er$ mém.). Recording the vibrations of a membrane was first accomplished by Leon Scott in 1857 by the invention of the “phonautograph,” which may be regarded as the precursor of the phonograph (Comptes rendus, 53, p. 108). This instrument consisted of a thin membrane to which a delicate lever was attached. The membrane was stretched over the narrow end of an irregularly-shaped funnel or drum, while the end of the lever or marker was brought against the surface of a cylinder covered with paper on which soot had been deposited from a flame of turpentine or camphor. The cylinder was fixed on a fine screw moving horizontally when the cylinder was rotated. The marker thus described a spiral line on the blackened surface. When sounds were transmitted to the membrane and the cylinder was rotated the oscillations of the marker were recorded. Thus tracings of vibrations were obtained. This instrument was much improved by Karl Rudolph König, of Paris, who also made with it many valuable observations. (See Nature, Dec. 26, 1901, p. 184). The mechanism of the recording lever or marker was improved by William Henry Barlow, in 1874, in an instrument called by him the “logograph” (Trans. Roy. Soc., 1874). The next step was König's invention of manometric flames by which the oscillations of a thin membrane under sound-pressures acted on a small reservoir of gas connected with a flame, and the oscillations were viewed in a rotating rectangular mirror, according to a method devised by Charles Wheatstone. Thus flame-pictures of the vibrations of sound were obtained (Pogg. Ann., 1864, cxxii 242, 660; see also Quelques experiences d'acoustique, Paris, 1882). Clarence Blake in 1876 employed the drumhead of the human ear as a logo graph, and thus obtained tracings similar to those made by artificial membranes and disks (Archiv. fur Öphthalmol., 1876, v. 1.). In the same year Sigmund Theodor Stein photographed the vibrations of tuning-forks, violin strings, &c. (Pogg. Ann., 1876, p. 142). Thus from Thomas Young downwards successful efforts had been made to record graphically on moving surfaces the vibrations of sounds, but the sounds so recorded could not be reproduced. This was accomplished by T. A. Edison in 1876, the first patent being dated January 1877.

In the first phonograph a spiral groove was cut on a brass drum fixed on a horizontal screw, so that when the drum was rotated it moved from right to left, as in the phonautograph. The recorder consisted of a membrane of parchment or gold-beater's skin stretched over the end of a short brass cylinder about 2 in. in diameter. In the centre of the membrane there was a stout steel needle having a chisel-shaped edge, and a stiff bit of steel spring was soldered to the needle near its point, while the other end of the spring was clamped to the edge of the brass cylinder over which the membrane was stretched. The recorder was then so placed beside the large cylinder that the sharp edge of the needle ran in the middle of the spiral groove when the cylinder was rotated. The cylinder was covered with a sheet of soft tinfoil. During rotation of the cylinder, and while the membrane was not vibrating, the sharp edge of the marker indented the tinfoil into the spiral groove; and when the membrane was caused to vibrate by sounds being thrown into the short cylinder by a funnel-shaped opening, the variations of pressure corresponding to each vibration caused the marker to make indentations on the tinfoil in the bottom of the groove. These indentations corresponded to the sound-waves. To reproduce the sounds the recorder was drawn away from the cylinder, and the cylinder was rotated backwards until the recorder was brought to the point at which it started. The cylinder was then rotated forwards so that the point of the recorder ran over the elevations and depressions in the bottom of the groove. These elevations and depressions, corresponding to the variations of pressure of each sound-wave, acted backwards on the membrane through the medium of the marker. The membrane was thus caused to move in the same way as it did when it was made to vibrate by the sound-waves falling upon it, and consequently movements of the same general character but of smaller amplitude were produced, and these reproduced sound-waves. Consequently the sound first given to the phonograph was reproduced with considerable accuracy. In 1878 Fleeming Jenkin and J. A. Ewing amplified the tracings made on this instrument by the sounds of vowels, and submitted the curves so obtained to harmonic analysis. (Trans. Roy. Soc. Edin. xxviii. 745). The marks on the tinfoil were also examined by P. F. F. Grutzner, Mayer, Graham Bell, A. M. Preece, and Lahr (see The Telephone, the Mzcrophone, and the Phonograph, by count du Moncel, London, 1884); also The Speaking Telephone and Talking Phonograph, by G. B. Prescott, New York, 1878).

The tinfoil phonograph, however, was an imperfect instrument, both as regards the medium on which the imprints were taken (tinfoil) and the general mechanism of the instrument. Many improvements were attempted. From 1877 to 1888 Edison was engaged in working out the details of the wax-cylinder phonograph. In 1885 A. G. Bell and S. Tainter patented the “graphophone,” and in 1887, Emile Berliner, a German domiciled in America, patented the “gramophone,” wherein the cylinder was coated with lampblack, and the friction between it and the stylus was made uniform for all vibrations. Incidentally it may be mentioned that Charles Cross deposited in 1877 a sealed packet with the Académie des Sciences, Paris, containing a suggestion for reproducing sound from a Scott phonautograph record. The improvements made by Edison consisted chiefly (1) in substituting for tinfoil cylinders or disks made of a waxy substance on which permanent records are taken; (2) in substituting a thin glass plate for the parchment membrane; (3) in improving the mechanical action of the marker; and (4) in driving the drum carrying the wax cylinder at a uniform and rapid speed by an electric motor placed below the instrument.

In the first place, permanent records can be taken on the wax, which is composed of stearin and paraffin. This material is brittle, but it readily takes the imprints made by the marker, which is now a tiny bit of sapphire. The marker, when used for recording, is shod with a chisel-shaped edge of sapphire; but the sapphire is rounded when the marker is used for reproducing the sound. The marker also, instead of being a stiff needle coming from the centre of the membrane or glass plate, is now a lever, weighted so as to keep it in contact with the surface of the wax. A single vibration of a pure tone consists of an increase of pressure followed by a diminution of pressure. When the disk of glass is submitted to an increase of pressure the action of the lever is such that, while