524 VOWELS AND CONSONANTS-STAMMERING. 
tlie act of preparation for sounding the succeeding consonant. 
The sound of the English i is a compound one, being formed 
in the act of transition from that of a in ah, to that of e as in 
theme ; hence it cannot be prolonged; and it is the very worst 
vowel sound upon which to sing a long note, since it is impos¬ 
sible to prevent its being heard as one of the sounds of which 
it is composed. Much discussion has taken place withr efer- 
ence to the true characters of the letters w and y, when 
employed to commence words, as wall , yawl , wet , yet. A little 
attention to the state of the mouth in pronouncing them will 
show, however, that they are then really vowel sounds, rapidly 
transformed into the succeeding ones; for the sound of w in 
this situation is oo ; and that of y is the long e ; so that wall 
might be spelt ooall, and yawl eaul. 
690. Consonants are naturally divided into those which 
require a total stoppage of the breath at the moment previous 
to their being pronounced, and which cannot therefore be 
prolonged ; and those in pronouncing which the interruption 
is partial, and which can be prolonged like the vow r els. The 
former are termed explosive consonants ; the latter continuous. 
The explosive consonants are b and p , d and t, the hard g and 
Jc. All the others are continuous ; but the sound is modified 
by the position of the tongue, palate, lips, and teeth ; and also 
by the degree in which the air is permitted to pass through 
the nose. 
691. The study of the mode in which the different conso¬ 
nants are produced, is of particular importance to those who 
labour under defective speech, especially that difficulty which 
is known as stammering. This very annoying impediment is 
occasioned by a want of proper control over the muscles con¬ 
cerned in articulation ; which are sometimes affected with a 
kind of spasmodic action. It is in the pronunciation of the 
consonants of the explosive class, that the stammerer usually 
experiences the greatest difficultyfor the total interruption 
to the breath which they occasion is frequently continued 
involuntarily, so that either the expiration is entirely checked, 
or the sound comes out in jerks. Sometimes, on the other 
hand, in pronouncing vowels and continuous consonants, the 
stammerer prolongs his expiration, without being able to 
check it. The best method of curing this defect (where there 
is no malformation of the organs of speech, but merely a want 
