It is a geometric system using straight lines and arcs written horizontally, vertically or diagonally to represent consonants.

The book is named after a line in a poem Vicious wrote some time after Nancy's death:

The line was "most likely" written by Ken Keeler.

The secretary took a piece of blank paper from his suit jacket, wrote some lines.

In notes included to the 1796 edition of Coleridge's poems, line 57 has written:

The true lines are not writing, nor speech either.

Never wrote me a line in his life.

- The first eight lines were plainly and strongly written, .

Lady Gillian was already at the stranger's side, lines of worry clearly writ on the smoothness of her brow.