The scale of these lectures does not require us to enter into a more detailed examination of the organs of speech and their product, articulate sounds, or a more exact definition of the physical relations of articulate sounds, than has thus been given. The principal and most frequent phonetic transitions are sufficiently explained by our alphabetic scheme. Let us notice a few of them.
The conversion of a surd letter into its corresponding sonant, or of sonant into surd, is abundantly illustrated in the history of every language. Our own plural sign, s, is pronounced as s only when it follows another surd consonant, as in plants, cakes; after a sonant consonant or a vowel, it becomes z, as in eyes, pins, pegs. A like change is common between two vowels, as in busy; the vowel intonation being continued through the intervening consonant; instead of intermitted during its utterance. So, on the other hand, we turn a d into a t after another surd consonant, where a sonant would be only with difficulty pronounced, as in looked (lookt); and the German eliminates the intonation from all his final mutes, speaking kind, kalb, as if they were written kint, kalp. Sounds of the same series, but of different classes, easily pass into one another: thus, the spirants (f, th, and so on) are almost universally derived from the full mutes, by a substitution of a close approximation (usually accompanied, it is true, by a slight shifting of position) for the full mute contact; and they
ment of the alphabet, please see the author's papers on the Standard Alphabet of Professor Lepsius, in the Journal of the American Oriental Society, vol. vii. pp. 299–332, and vol. viii., pp. 335–373. The signs used in the scheme are those of the Lepsian system. Thus, a represents the sound in fār; 
, in făt; e, in thĕn and thēy; i, in pĭn and pīque; ḁ, in whăt and āll; o, in nōte; u, in fŭll and rūle; 
, in bŭn and būrn; ž, the z of azure; š, the sh of shun; δ, the th of that; θ, the th of thin. The distinction of long and short vowels, although it is in every case founded on a difference of quality as well as quantity, is here, for convenience's sake, omitted; as are also the diphthongs ai, au, and ḁi, as in pint, pound, point (of which the two first are rather vocal slides than diphthongs). The compound consonants ch and j, in church, judge, have also strictly a right to separate representation; since, though their final element respectively is š and ž, their initial element is not precisely our usual t and d, but one of another quality, more palatal. Were all these differences of utterance noted by separate characters, our written alphabet would contain fourty-two signs, instead of the thirty given above.
