On the Articulation of the Human Voice. 159 
mencement of syllables; and even in this action nearly similar 
effects can be produced by vowel sounds. 
It will be observed in the several diagrams of words and sen- 
tences that in syllables commencing with the labials P, B, and M 
there is a tendency to a slight rise in the pre-pause just before 
the consonant action begins, and that the diagrams of T, D, and N 
show a slight fall, or negative action, in the pre-pause, and that 
in K and G (hard) there is a strong negative action. 
The diagrams of M and N are of much less vertical height than 
those of other consonants, in consequence of a considerable quan- 
tity of the air passing through the nose. 
In the diagrams of the pneumonic letters F, V,S, Sh, Th sharp, 
and Th flat there is considerable variation of form depending on 
the quickness with which they are pronounced; but the general 
form of the diagrams of F, V, 8, and Sh is curved. That of Th 
is nearly vertical. 
COMBINED AND COMPOUND CONSONANTS. 
The mechanism of the mouth permits of some consonant actions 
being combined with others ; in some cases, however, the conjoined 
consonants form compounds rather than combinations ; but the 
actions follow each other so quickly that they sound to the ear 
as if combined. 
They may be divided into three classes :— 
1. Those which can only be used positively—that is, with a 
vowel sound following, as br, bl, gr, kl, &e. 
2. Those which can only be used negatively—that is, with 
a vowel sound preceding, as mp, nt, kt, pt, &e. 
3. Those which can be used either positively or negatively, 
as sp, st, sk, &e. 
In class 1 the presence of both actions is plainly visible in the 
diagrams. 7 
In class 2 the re-actions are those of the last consonant, but 
generally rendered with greater force than the reactions of tho 
same consonants when preceded by a vowel sound only. 
In class 3, if the vowel sound precedes, as in esp, est, esk. 
est, esp, esk, 
x 
the combination is complete, and the re-action strong. 
* The mark * signifies the re-action. 
