I'm familiar with the SH "Trumpet" (very difficult) because I'm a shape note singer here in the USA. I met some of you folks when you came to our convention a number of years ago - hence my interest in WG music. I think, however that this piece is more likely the Dixon hymn mentioned by Tim.
This is probably another red herring, but in the 1991 revision of the Sacred Harp, tune 149 is called The Trumpet, with composer given as J. Williams, 1831. Its metre is 22.214.171.124, with verses... more