This script is very much a Phonological Cypher, being an easily hand-written, phonetically constructed alphabet like others in that series. The name is derived from an interesting whistling effect arising from a rounded voiced bilabial fricative followed by a high front vowel. In this script, the name also has a geometric symmetry. Each letter is drawn using one stroke of the pen.
Consonants have place and manner shown by the front stem and following tails respectively. The series are almost regularly formed. The 3rd and 4th columns are for common fricatives, while the last two columns hold more complex or less common fricatives. The semivowels and flap lie outside the main pattern. The 2nd letter of the 4th row is a prefix to be used with semivowels or other phonemes needing (extra) aspiration or devoicing.
The vowel letters form a geometric series, and have a four-level front-back structure, with rounding for each position. The third row is considered to be central, whilst the top row is extra high. Narrowing diphthongs can use the [j] and [w] letters as the second element.
This is the first line of Shakespeare’s sonnet 18, for comparison with versions of SIGIL etc.
Shall I compare thee to a summerís day?