2.5.1. Syllables are distinguished according to the length of time required for their pronunciation. Two degrees of Quantity are recognized, long and short.
NOTE. In syllables, quantity is measured from the beginning of the vowel or diphthong to the end of the syllable.
2.5.3. A syllable is long usually,
a. if it contains a long vowel; as, ma-ter, dn-ghu
b. if it contains a diphthong; as, Eu-ro-pa, mn-io
c. if it contains any two non-syllabic consonants (except a mute with l or r)
2.5.4. A syllable is short usually
a. if it contains a short vowel followed by a vowel or by a single consonant; as, cei
b. if it contains a vocalic sonant; as, /'rt-kos/, /no-m'n/, /de-k'm/
2.5.5. Sometimes a syllable varies in quantity, viz. when its vowel is short and is followed by a mute with l or r, i.e. by pl, kl, tl; pr, kr, tr, etc.; as, agri . Such syllables are called common. In prose they are regularly short, but in verse they might be treated as long at the option of the poet.
NOTE. These distinctions of long and short are not arbitrary and artificial, but are purely natural. Thus, a syllable containing a short vowel followed by two consonants, as ng, is long, because such a syllable requires more time for its pronunciation; while a syllable containing a short vowel followed by one consonant is short, because it takes less time to pronounce it. In case of the common syllables, the mute and the liquid blend so easily as to produce a combination which takes scarcely more time than a single consonant. Yet by separating the two elements (ag-ri) the poets are able to use such syllables as long.