One of nine

Dundee has a large university hospital called Ninewells. I had never even thought about the name until we visited Dundee Botanical Gardens. While we were looking at this corner of the garden, a member of staff informed us that it was the last of the nine wells!! He didn’t know what happened to the other eight. Something to google about when we get home.
The circular panel is an oil painting of lichen by an artist exhibiting in the gardens.