The first linguist who tried to describe and classify vowels for
all languages was D. Jones. He devised the system of 8 Cardinal
Vowels. The basis of the system is physiological. Cardinal vowel
No. 1 corresponds to the position of the front part of the tongue
raised as closed as possible to the palate. The gradual lowering of
the tongue to the back lowest position gives another point for
cardinal vowel No.5. The lowest front position of the tongue gives
the point for cardinal vowel No.4. The upper back limit for the
tongue position gives the point for cardinal No.8. These positions
for Cardinal vowels were copied from X-ray photographs. The tongue
positions between these points were X-rayed and the equidistant
points for No.2, 3, 6, 7 were found. The IPA symbols (International
Phonetic Alphabet) for the 8 Cardinal Vowels are: 1 -i, 2 - e, 3 -
ε, 4 - a, 5 - a:, 6 - , 7 - o, 8 - u.
The system of Cardinal Vowels is an international standard. In
spite of the theoretical significance of the Cardinal Vowel system
its practical application is limited. In language teaching this
system can be learned only by oral instructions from a teacher who
knows how to pronounce the Cardinal Vowels.
Russian phoneticians suggest a classification of vowels according
to the following principles: 1) stability of articulation; 2)
tongue position; 3) lip position; 4) character of the vowel end; 5)
length; 6) tenseness.
1. Stability of articulation. This principle is not singled out by
British and
American phoneticians. Thus, P. Roach writes: "British English (BBC
accent) is
generally described as having short vowels, long vowels and
diphthongs". According to Russian scholars vowels are subdivided
into: a) monophthongs (the tongue position is stable); b)
diphthongs (it changes, that is the tongue moves from one position
to another); c) diphthongoids (an intermediate case, when the
change in the position is fairly weak).
Diphthongs are defined differently by different authors. A.C.
Gimson, for example, distinguishes 20 vocalic phonemes which are
made of vowels and vowel
glides. D. Jones defines diphthongs as unisyllabic gliding sounds
in the articulation of which the organs of speech start from one
position and then elide to another
position. There are two vowels in English [i:, u:] that may have a
diphthongal glide where they have full length (be, do), and the
tendency for diphthongization is becoming gradually stronger.
2. The position of the tongue. According to the horizontal movement
Russian phoneticians distinguish five classes: 1) front; 2)
front-retracted; 3) central; 4) back; 5) back-advanced.
British phoneticians do not single out the classes of
front-retracted and back-advanced vowels. So both [i:] and [i] are
classed as front, and both [u:] and [Y] are classed as back.
The way British and Russian phoneticians approach the vertical
movement of the tongue is also slightly different. British scholars
distinguish three classes of vowels: high (or close), mid (or
half-open) and low (or open) vowels. Russian phoneticians made the
classification more detailed distinguishing two subclasses in each
class, i.e. broad and narrow variations of the three vertical
positions. Consequently, six groups of vowels are
distinguished.
English vowels and diphthongs may be placed on the Cardinal Vowel
quadrilateral as shown in Figs. 2, 3, 4.
3. Another feature of English vowels is lip position. Traditionally
three lip positions are distinguished, that is spread, neutral,
rounded. Lip rounding takes place rather due to physiological
reasons than to any other. Any back vowel in English is produced
with rounded lips, the degree of rounding is different and depends
on the height of the raised part of the tongue; the higher it is
raised the
more rounded the lips are.
4. Character of the vowel end. This quality depends on the kind of
the articulatory transition from a vowel to a consonant. This
transition (VC) is very closed in English unlike Russian. As a
result all English short vowels are checked when stressed. The
degree of checkness may vary and depends on the following
consonants (+ voiceless - voiced - sonorant -).
5. We should point out that vowel length or quantity has for a long
time been the point of disagreement among phoneticians. It is a
common knowledge that a vowel like any sound has physical duration.
When sounds are used in connected speech they cannot help being
influenced by one another. Duration of a vowel depends on the
following factors: 1) its own length; 2) the accent of the syllable
in which it occurs; 3) phonetic context; 4) the position in a
rhythmic structure; 5) the position in a tone group; 6) the
position in an utterance; 7) the tempo of the whole utterance; 8)
the type of pronunciation. The problem the analysts are concerned
with is whether variations in quantity are meaningful (relevant).
Such contrasts are investigated in phonology.
There is one more articulatory characteristic that needs our
attention, namely tenseness. It characterizes the state of the
organs of speech at the moment of vowel production. Special
instrumental analysis shows that historically long vowels are tense
while historically short are lax.