"W" is for Walker, William [1809-1875]. Teacher, composer, author. In 1835, the man known as "Singing Billy" Walker published Southern Harmony, a shaped-note hymnal using a four-shape [fa-so-la] system. The shaped-note style is a simplified musical notation-- developed to make it easier for untrained congregations to sing in harmony without instrumental accompaniment.
Shapes [triangle = fa; oval = so; rectangle = la; and diamond = mi] were added to the note heads to help singers find pitch within major and minor scales. Southern Harmony was immensely popular throughout the South, going through several editions and sold more than 600,000 copies. Among the hymns was first publication of the tune "New Britain," with the words "Amazing Grace." William Walker's shaped-note style is still used today and the annual "Big Singing" in Benton, Kentucky attracts large crowds.