HYMN 591 Savior like a Shepherd Lead Us - Tune RHUDDLAN

I have a question about the tune RHUDDLAN.
The following info is on your site.
Tune Information:
RHUDDLAN is a traditional Welsh tune used by harp-playing folk musicians. Named after the historic village in northern Wales, the tune was published in the musical edition of Edward Jones's Musical and Poetical Relicks of the Welsh Bards (1800).
I have looked for this tune in the above mentioned edition and find only the Morva Rhuddlan (The Marsh of Rhuddlan) listed on page 143 of the book. This however, is not the tune.
I have entered here information from the Welsh Biography Online, which shows that the RHUDDLAN hymn tune was composed by John Evans b 1770
EVANS , JOHN ( 1770 - 1851 ), land surveyor, schoolmaster, and musician ; b. at Rhuddlan, Flints. His father was parish clerk of Rhuddlan , and the son followed the same occupation for a while. When 16 years old he opened a school to which pupils came from considerable distances to receive instruction in arithmetic and navigation . He published two works called Cyfrifydd Parod (i.e. ready reckoner) — the one for the use of persons buying and selling grain, the other for use in measuring timber and haystacks. He was a good musician and played the ‘cello in church . His anthem ‘ O deuwch i'r dyfroedd ,’ and his hymn-tunes ‘ Myfyrdod ’ and ‘ Rhuddlan ,’ became popular. He prepared a work on ‘ Thorough Bass ’ and collected together some hymn-tunes for publication , but all these were lost on their way to the printer . He d. 31 March 1851 .

As John Evans is an ancestor of mine I am anxious for clarification.
Many thanks in anticipation of your answer.