lexical and syntactic character of a line's syllables, which results in stress; rather than a representation of stress levels themselves. Ictus (S for "strong") and nonictus (w for "weak") have constraints on which syllable statuses can fill them. These rules for matching syllable status and metrical position are called "mapping rules", and strict (e.g. Alexander Pope) versus loose (e.g. William Shakespeare) styles of iambic pentameter can be defined by applying different mapping rules. Further, while his metrical scansion begins as a familiar wSwSwSwSwS, he allows "w" and "S" to trade places under certain conditions, and when they do their mapping rules are altered, requiring additional symbols. In the first (rhythmic) line of scansion, syllables that impinge on their neighbors are connected by hyphens; in the second (metrical) line, positions that have switched places and therefore altered their mapping rules are connected by hyphens. When to the sessions of sweet silent thought A---Ō o—A—o Ō----a----A-o A Ś---w w S w W----s S w S Other methods of scansion Musical scansion In 1880, Sidney Lanier published The Science of English Verse, in which he developed a novel theory exploring the connections between musical notation and meter in poetry. Although some figures such as T.S. Osmond and Harriet Monroe praised it, others did not view it kindly. For example, Vladimir Nabokov in his Notes on Prosody says: "In my casual perusals, I have of course slammed shut without further ado any such works on English prosody in which I glimpsed a crop of musical notes." (pages 3–4) Harvey Gross' criticism also described the theory as lacking in good sense, saying "it scatters sand in the eyes and pours wax in the ears." One account cited that musical scansion was an experimental technique during the nineteenth century but was obscured by the then existing conventional scansion. An interpretation of the notion of musical scansion states three theories: 1) beats occur at regular intervals of time; 2) syllables of a verse can be grouped in measures or "bars"; and 3) beats form a hierarchy of strength. Robert Bridges George R. Stewart Stewart's notation influenced John Crowe Ransom and John Thompson, though they did not use his full roster of symbols. Generative metrics Other symbols The metrical triseme (⏗), tetraseme (⏘) and pentraseme (⏙) occur in the Miscellaneous Technical section of the Unicode standard and appear to be used in scansion. Bibliography Maxwell, Ian. Scansion Scanned.