A basic seven-line staff has a bold middle line representing C and top and bottom lines that both represent F#/Gb. Two ledger lines appear below this staff, followed by a dashed line also representing C. From the dashed C line to the F#/Gb line at the top of the staff is a span of about an octave and a half. On the piano staff the line pattern is symmetrically repeated below the dashed line: another two ledger lines followed by another seven line staff just like the one above. Traditional noteheads are used.
Earliest documentation: 1897
Source: Directory of Music Notation Proposals, section/page: 13/96