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Show 112 Additional Notes. organ-pipe about t\VO thirds of it are be!ie~ed to .pass on tl~e outside of this edge, and one third to pass on the ms1de of 1t; but t~us cur~·ent of air on the inside forms an eddy, whether the bottom of the p1pc be closed or not; which eddy returns upwards, and strikes by quick intervals ao·ainst the original stream of air, as it falls on the edge of the aperture~ and forces outwards this current of air with quick repetitions, so as to make more than two thirds of it, and less than two third al~ ternately pass on the outside; whence a part of this stream of air, on each side of the edge of the aperture is perpetually stopped by that edge; and thus a vacuum and vibration in consequence, are recipro~ cally produced on each side of the ed.ge o~ the apert.ure. . The quickness or slow11 ess of these VIbrations constitute the htgher and lower notes of music, but they all of them are propagated to distant places in the same time; as the low notes of a distant ring of bells are beard in equal times with the higher ones: hence in speakino · at a distance from the auditors, the dear sounds produced in the la1~ynx by the quick vibrations of its aperture, which .form the v~wels; the tremulous sounds of the L. R. :!VI. N. NG. wh1ch arc owmg to vibrations of certain apertures of the mouth and nose, and are so slow, that the intervals between them are perceived; the sibilant sounds, which 1 1:mpptn;e are uGct!.~toOl;(l 1Jy the air uut .rushing iuto a Gumplete vacuum, whence the vibrations produced are defective in veluGity; and lastly the very high notes made by the quickest vibrations of the lips in whistling; are all heard 1n due succession without confusion; as the progressive motions of all sounds I believe travel with equal velo• city, notwithstanding the greater or less quickness of their ·vibration&. III. STRUCTURE OF THE ALPHABE':t'. Mute and antesonant Consonants, and nasal Liquids. P. If the lips be pressed close together and some air be condensed in the mouth behind them, on opening the lips the mute consonant P begins a syllable; if the lips l)e dosed suddenly during the passage of a current of air through thcn1, the air becomes Analysis if A1·ticulate Sou11ds. 113 condensed in the mouth behind them, and the mute consonant P terminates a syllable. B. If in the above situation of the lips a sound is previously produced in the mouth, which may be termed orisonance, the semisonant consonant ll is produced, which like the letter P above described may begin or terminate a yllable. l\1. In the above situation of the lips, if a sound is produced through the nostrils, which sound is termed narisonance the nasal ' letter l\1 is formed; the sound of which may be lengthened in pronunciation like those of the vowels. T. If the point of the tongue be applied to the forepart of the palate, at the roots of the upper teeth, and some air condensed in the mouth behind, on withdrawing the tongue downwards the mute consonant T is formed; which may hegin or terminate a syllable. D. If the tongue be placed as above described, and a sound be previously prod ucecl j n the mouth, the semisonant consonant Dis formed, which may begin or terminate a syllable. N. If in the above situation of the tongue and palate a sound be produced through the J1ostrils, the nasal letter N is formed, the sound of which may be elongated like those of the vowels. K. If the point of the tongue be retracted, and applied to the middle part of the palate; and some air condensed in the mouth behind; on withdrawing the tongue downwards the mute consonant K is produced, which may begin or terminate a syllable. Ga. If in the above situation of the tongue and palate a sound be previously produced in the mouth behind, the semisonant consonant G is formed, as pronounced in the word go, and may begin or terminate a syllable. ~G. If in the above situation of the tongue and palate a sounJ be produced through the nostrils; the nasal letter n g is produced, as in king and throng; which is the french n, the sound of which may be elongated like a vowel; and should have an appropriated character, as thus m. Three of these letters, P, T, K, are stops-to tl1e stream of vocal air, and are called mutes by grammarians; three, B, D, Ga, are preceded by a little orisonance; and three, M, N, NG, possess continued narisonance, and have been called liquids by grammarians. Q |