, Natural, [307], [340]

, Oral language, not proportioned to development of, [293], [314]

, Permanence of, [329]

, Power of, compared with speech, [347], [349]

, Surviving in gesture, [330]

, Symmorphs in, [343]

, Synonyms in, [341]

, Systematic use of, distinguished from uniformity of, [330]

, Theories of Indians, respecting the, [313]

Silence, Sign for, [304]