242 Proceedings of Royal Society of Edinburgh. [sess. 
sible to the oral resonance of the vowels covers largely the same 
ground as the range possible to the several resonances of each of 
the spirate fricatives themselves. And the reason is not far to 
seek. 
In Phonetische Studien , vol. iii. p. 264, I showed that the 
mechanism which produces the declining scale of resonance ex- 
hibited in this table is precisely that which has been seen to vary 
the resonance of each of these spirate fricative consonants. The 
oral articulation of close i is a pipe-like passage along the palate, 
about 50 mm. long. This passage increases up to open e, when it 
is about 100 mm. long. The further fall of resonance is produced 
step by step, by bulging the passage, and contracting gradually its 
two apertures — the labial, by which it opens into the outer air, and 
the velar, by which it communicates with the pharynx. The 
diagrams in Journal of Anat. and Phys. } vol. xxxi., show the 
same thing. 
The passage in which these modifications are made is almost 
identically the same passage in which, by similar modifications, 
the resonance of each spirate fricative has been conducted through 
a series of similar changes (see ante). There is, therefore , as a 
rule, for every spirate fricative, a possible articulation approximat- 
ing more or less closely, in resonance, form, and position, to the 
oral articulation of any vowel which may happen to be adjacent to 
it. 
ftecurring now to combinations of the type found to be simplest 
( asa , oho , ifi, etc.), it is evident, from the principle of economy, 
that the articulation of a consonant so situated will depart as little 
as possible from that of the vowel by which it is flanked on both 
sides. But when it is asked how much this least possible amounts 
to, the answer varies somewhat with the vowel, and still more with 
the consonant. There is one region of the articulation, however, 
where the same things happen always in combinations of this 
class; this is the pharyngeal region. Four things always happen 
there, the closing of the larynx to form the first vowel, the opening 
of it to form the consonant, the closing of it again for the second 
vowel, and the opening of it at the finish. It is the second and 
third of these four which concern us here, because they help to 
create the on-glide and the off-glide, respectively, of the fricative 
