The lateral approximant in General British English (GB) is realised as light when occurring in the onset (leaf), and as dark in the rhyme (help, feel, google). Non-prevocalic positions are typical contexts for lenition, analysed in Element Theory as decomposition in weak positions. However, it is unclear how velarisation can be characterised as element loss if light [l] is represented as |A I|, while dark [ɫ] is represented as |A U|. Therefore, I propose that laterals in GB contain both the coronal |I| and the velar |U| element underlyingly (in addition to |A|), but because these cannot combine in a compound segment in English, they are both floating. Their association at the phrase level is determined by the apophonic chain (Guerssel & Lowenstamm 1996), mapped onto the structure of the syllable: |I| is attracted to the prevocalic position, |A| to the vocalic position and |U| to the postvocalic position. Darkening thus does not involve lenition of /l/, but partial interpretation in all positions. In contrast, I analyse vocalisation of dark [ɫ] as lenition, involving loss of |A| in weak positions. I integrate the lateral into the system of glides in English, and establish a typology of its behaviour across different accents.