A final consonant, when it is not preceded by a single vowel, or when the accent is not on the last syllable, should remain single before an additional syllable: as, toil, toiling; oil, oily; visit, visited; differ, differing; peril, perilous; viol, violist; real, realize, realist; dial, dialing, dialist; equal, equalize, equality; vitriol, vitriolic, vitriolate.

Dr. Webster, with apparent propriety, writes caviling and cavilous with one l, like dialing and perilous; but he has in general no more uniformity than Johnson, in respect to the doubling of l final.