These cookies are absolutely essential for our website to function properly.
We use Google Analytics to measure how you use the website so we can improve it based on user needs.
These cookies may be set by third party websites and do things like measure how you view YouTube videos.
Amgueddfa Cymru – Museum Wales
Single page, typed in black ink on cream paper. Results of tests on the manufacture of Dowlais tap-hole clay containing "nettle" fireclay. Dated 14/4/50.