The manufacture of kelp in Ireland from the 17th to early 20th centuries provided soda and later iodine for contemporary industries. It was an immensely important element of coastal economies, and notably for island communities, often impoverished and with limited agricultural means. Edit 09/11/22: Spoiler picture added in lieu of hint. Please place cache back exactly as placed.
This cache has been adopted so that it will live on. In memory of a good friend. Alan Shiel “Hezekiah” 1950 -2014