Four-character carve-up of 'Um-bridge':
乌 (wū) for 'Um-',
姆 (mǔ) for the '-m-' (Chinese has no syllable-final 'm' in pinyin, so it gets re-syllabified),
里 (lǐ) for '-bri-',
奇 (qí) for '-(d)ge'. The
姆 character is the workhorse for English '-m-' or '-mer-' inside foreign names (
汤姆 Tom,
山姆 Sam).