As Chomsky and Halle point out (1968: 318), the specification of [1] in terms of the continuant-noncontinuant scale is problematic. At first sight one would consider it [+ continuant], since there is no total blockage of air flow through the mouth. It can, however, be taken as [— continuant] if the defining criterion of “stop” (= “noncontinuant”) is stated as the blockage of air flow past the primary stricture, i.e. a complete closure in the sagittal plane of the oral cavity. Evidence exists in support of both points of view; Chomsky and Halle adduce data from Chippewyan in favour of treating [1] as continuant and data from “certain dialects of English spoken in Scotland” in favour of taking it as noncontinuant. For the latter they refer to Lloyd, 1908, as attesting the use of “lax diphthongs” before noncontinuants and [1], but “tense diphthongs” before continuants and [r].