The Sheet music is in the Library of Congress Collection dated 1871 and giving credit to Elizabeth Stirling.

The tune is, in places, remarkably similar to the Mike Gabriel one, except that the first two lines of each verse are repeated and the chorus ends ...
"WHEN THE FREE AND HAPPY BARLEY IS SMILING ON THE SCYTHE"

I have "The Fellowship Songbook" printed in 1915 which contains the same version.