Wikipedia
Merthyr (UK Parliament constituency)
Merthyr was a borough constituency centred on the town of Merthyr Tydfil in Wales. It returned one Member of Parliament to the House of Commons of the Parliament of the United Kingdom.
The constituency was created for the 1918 general election, and abolished for the 1950 general election, when it was largely replaced by the new constituency of Merthyr Tydfil.