Complex sentence: The melody is described in "Songs of the Isles" as a "traditional Gaelic tune (probably Lochaber) arranged by Hugh S Roberton", however the original tune was a pipe tune, "Creag Guanach"; from Lochaber.
Split into simpler sentences: The melody is described in "Songs of the Isles" as a "traditional Gaelic tune (probably Lochaber) arranged by Hugh S Roberton". In fact, the original tune was a pipe tune, "Creag Guanach"; from Lochaber.