first syllable, as légible, théatre, except discíple, and some words which have a position, as exámple, epístle.
13. Trissyllables in ude commonly accent the first syllable, as plénitude.
14. Trissyllables ending in ator or atour, as creátour; or having in the middle syllable a diphthong, as endeávour; or a vowel before two consonants, as doméstick; accent the middle syllable.
15. Trissyllables that have their accent on the last syllable are commonly French, as acquiésce, repartée, magazíne, or words formed by prefixing one or two syllables to an acute syllable, as immatúre, overchárge.
16. Polysyllables, or words of more than three syllables, follow the accent of the words from which they are derived, as árrogating, cóntinency, incóntinently, comméndable, commúnicableness. We should therefore say dispútable, indispútable; rather than dísputable, indísputable; and advertísement, rather than advértisement.
17. Words in ion have the accent upon the antepenult, as salvátion, perturbátion, concóction; words in atour or ator on the penult, as dedicátor.
18. Words ending in le commonly have the accent on the first syllable, as ámicable, unless the second syllable have a vowel before two consonants, as combústible.
19. Words ending in ous have the accents on the antepenult, as uxórious, volúptuous.
20. Words ending in ty have their accent on the antepenult, as pusillanímity, actívity.
These rules are not advanced as complete or infallible, but proposed as useful. Almost every rule of every language has its exceptions; and in English, as in other tongues, much must be learned by example and authority. Perhaps more and better rules may be given that have escaped my observation.