Who is the author of the hymn "What sacred fountain?" I've heard of William Irons but also a Joseph Irons.
Where did you find even that much attribution? I don't see an author listed for any of the three instances.
I found it in Gadsby's Hymns, as hymn No. 1156. (https://bethlehemswell.com/hymns/1156/) The problem is that we don't have Gadsby's Hymns on Hymmary, so "What Sacred Fountain" isn't listed as J. Irons' composition. I can't seem to find the "William Irons" attribution anymore, but I suspect that is a mistake.
According to the Cambridge Dictionary of Hymnology (https://hymnology.hymnsam.co.uk/w/william-josiah-irons), the author is William J. Irons.
I guess that solves it.
What edition does that website have? According to Julian it only went up to hymn no. 1138 in his son's 1882 (posthumous) edition.
Clearly IMO this hymnal ought to be in our database.