January 6, 1923] 
NATURE 23 

already described, they may be placed in parallel— 
side by side—with a single larynx having a forked or 
bifurcated passage to communicate with each of them. 
Two models made on this principle—one tuned to give 
i (eat) ¢d’’’’2434 and f'342 and the other to give A (up) 
g’’1534 and ¢g”8r2—when blown emit vowel sounds 
ractically the same as those given by the correspond- 
ing resonators in series with a single mouth. 
Certain vowel sounds can be produced by a single 
cylindrical or ovoid resonator. An egg-shaped plas- 
ticine resonator, when blown through by means of a 
small hole at the back, gave three resonances—c"512, 
g’”’1534, and c’’’’2048, and a vowel sound intermediate 
between e (men) and & (earth). 
Double resonances may also be obtained from a 
cylindrical resonator closed at one end 
and blown through a small orifice in the 
closed end. A _ reed-actuated cylindrical 
resonator of variable length (lent by Prof. 
D. Jones) gave a series of vowel-like sounds, 
and a plasticine cylindrical resonator gave 
A (up) with resonances #g’"1625 and #g”812. 
These cases of double resonances pro- 
duced by a single resonator are interesting 
as affording a possible explanation of 
Helmholtz’s statement, that he had 
obtained certain vowel sounds by the use 
of a single resonator. 
The reproduction of the various consonants 
appears to depend on exactly the same 
principles, namely, the combination of 
separate resonators (sometimes more than 
two), and it has been found possible to 
reproduce all the English consonant sounds 
also in this way. The principal difference is that, 
whereas with the vowels (other than the diphthongs) 
the resonances are more or less fixed during the 
voicing of each vowel, with most of the consonants 
the resonances are rapidly changing, and the con- 
sonant sound depends to a large extent on the rate 
of change. 
To summarise these experiments and conclusions: 
We have seen that each of the English vowel sounds, 
when whispered or breathed, appears to consist of two 
musical notes due to the air current from the lungs 
blowing through the cavity of the mouth and throat. 
The cavity as a whole is divided up by the tongue 
into two resonating cavities—one behind the other— 
each of which produces its characteristic note. 
When, instead of passing a steady current of breath 
through these resonators, we pass a current of air 
which has previously been set in vibration by the 
action of the larynx, the sound of the larynx note is 
coloured by the two resonators respectively and 
acquires the character which we recognise as voiced 
vowel sound. 
The two resonances which characterise each of the 
different vowel sounds are not absolutely fixed in pitch 
for each vowel sound but may vary over several semi- 
tones ; the tuning of the resonances is performed, in 
the mouth, mainly by the action of the tongue and 
lips, and is quite independent of the vibrations of the 
larynx. 
In models, the double resonance of the human 
mouth can be reproduced by pairs of Helmholtz 

Fic. 3.—Plasticine resonators. 
resonators joined together in series (making proper 
allowance for the reaction of each resonator on the 
resonating pitch one of the other) or by placing the 
resonators in parallel, side by side, so as to produce 
a double-mouthed model. When the resonators are 
driven tandem, the leader and wheeler may be counter- 
changed—so that, for example, the lower resonance 
is given by the front resonator instead of by the back, 
and vice versa. 
It follows that it should be possible to write down any 
vowel sound in musical notation, and to reproduce it by 
means of a suitable instrument designed to give any 
required pair of resonances, either in series or in 
parallel. It also follows that every one who can 
recognise vowel sounds must have a perfect ear for 
music, and an almost absolute sense of musical pitch. 
Obituary. 
C. L. WracceE. 
BY the recent death of Mr. Clement L. Wragge, 
formerly head of the Weather Bureau at Brisbane, 
at Auckland, New Zealand, meteorology has lost an 
enthusiastic worker, Mr. Wragge was born at Stour- 
bridge on September 18, 1852, and was educated at 
Uttoxeter Grammar School. After a short period of 
service in the Surveyor-General’s department at 
Adelaide, he returned to England, where he founded 
several meteorological stations in North Staffordshire. 
NO. 2775, VOL. 111] 
When the Scottish Meteorological Society wished to 
establish a meteorological observatory on Ben Nevis 
at 4400 feet above sea level, they were fortunate in 
securing the services of Mr. Wragge, who during the 
summers of 1881 and 1882 daily ascended the mountain 
and took regular observations. The Scottish Meteoro- 
logical Society, in an appeal for public funds to found a 
permanent observatory on Ben Nevis, referred to “ the 
observations made by Mr. Wragge with such skill, 
endurance, and enthusiasm during the last two summers 
on Ben Nevis.” That very considerable endurance was 
