distinction between the quantity of vowels, but in Latin of course a given
vowel was either long or short, and literary tradition became so fixed in
this matter that the professional poets of the Augustan age do not
tolerate any deviation from it. There are indications, however, that the
common people did not observe the rules of quantity in their integrity. We
can readily understand why that may have been the case. The comparative
carelessness, which is characteristic of conversation, affects our
pronunciation of words. When there is a stress accent, as there was in
Latin, this is especially liable to be the case. We know in English how
much the unaccented syllables suffer in a long word like "laboratory." In
Latin the long unaccented vowels and the final syllable, which was never
protected by the accent, were peculiarly likely to lose their full value.
As a result, in conversational Latin certain final consonants tended to
drop away, and probably the long vowel following a short one was regularly
shortened when the accent fell on the short syllable, or on the syllable
which followed the long one. Some scholars go so far as to maintain that
in course of time all distinction in quantity in the unaccented vowels was
lost in popular Latin. Sometimes the influence of the accent led to the
excision of the vowel in the syllable which followed it. Probus, a
grammarian of the fourth century of our era, in what we might call a
"Guide to Good Usage"[20] or "One Hundred Words Mispronounced," warns his
readers against masclus and anglus for masculus and angulus. This is the
same popular tendency which we see illustrated in "lab'ratory."

The quality of vowels as well as their quantity changed. The obscuring of
certain vowel sounds in ordinary or careless conversation in this country
in such words as "Latun" and "Amurican" is a phenomenon which is familiar
enough. In fact a large number of our vowel sounds seem to have
degenerated into a grunt. Latin was affected in a somewhat similar way,
although not to the same extent as present-day English. Both the ancient