OBS. 10.—­How “precise” was Sheridan’s idea of accent, the reader may well judge from the foregoing quotations; in four of which, he describes it as “a certain stress,” “the stress,” and “stress only,” which enforces some “letter;” while, in the other, it is whimsically made to consist in two different modes of pronouncing “syllables”—­namely, with equability, and with precipitance—­with “dwelling longer,” and with “smarter percussion”—­which terms the author very improperly supposes to be opposites:  saying, “For the two ways of distinguishing syllables by accent, as mentioned before, are directly opposite, and produce quite contrary effects; the one, by dwelling on the syllable, necessarily makes it long; the other, by the smart percussion—­of the voice, as necessarily makes it short”—­Ib., p. 57.  Now it is all a mistake, however common, to suppose that our accent, consisting as it does, in stress, enforcement, or “percussion of voice,” can ever shorten the syllable on which it is laid; because what increases the quantum of a vocal sound, cannot diminish its length; and a syllable accented will always be found longer as well as louder, than any unaccented one immediately before or after it.  Though weak sounds may possibly be protracted, and shorter ones be exploded loudly, it is not the custom of our speech, so to deal with the sounds of syllables.

OBS. 11.—­Sheridan admitted that some syllables are naturally and necessarily short, but denied that any are naturally and necessarily long.  In this, since syllabic length and shortness are relative to each other, and to the cause of each, he was, perhaps, hardly consistent.  He might have done better, to have denied both, or neither.  Bating his new division of accent to subject it sometimes to short quantity, he recognized very fully the dependence of quantity, long or short, whether in syllables or only in vowels, upon the presence or absence of accent or emphasis.  In this he differed considerably from most of the grammarians of his day; and many since have continued to uphold other views.  He says, “It is an infallible rule in our tongue that no vowel ever has a long sound in an unaccented syllable.”—­Lectures on Elocution, p. 60.  Again:  “In treating of the simple elements or letters, I have shown that some, both vowels and consonants, are naturally short; that is, whose sounds cannot possibly be prolonged; and these are the [short or shut] sounds of e, i, and u, of vocal sounds; and three pure mutes, k, p, t, of the consonant; as in the words _beck, lip, cut_.  I have shown also, that the sounds of all the other vowels, and of the consonant semivowels, may be prolonged to what degree we please; but at the same time it is to be observed, that all these may also be reduced to a short quantity, and are capable