However , the 1867 Act had only a limited impact in Glamorgan as the majority of the population lived in the county constituency .
Reflecting the increased importance and wealth of Merthyr the borough was given a second MP after the Reform Act 1867 .
The Reform Act 1867   had only a limited impact in Glamorgan as the majority of the population lived in the county constituency .
Reflecting the increased importance and wealth of Merthyr the borough was given a second MP after the Reform Act 1867 .