sentences:  Even thereafter, the immediate interest appeared to be in who would occupy the second seat rather than whether or nor Bruce would be re-elected.The Merthyr element of the constituency had dominated the representation since its formation in 1832 but in recent years the population of the neighbouring Aberdare valley had grown considerably, mainly as a result of the development of the steam coal trade, that they should determine the identity of the second member.The Merthyr electorate had traditionally been far larger than that of Aberdare but by 1868, Aberdare's electorate formed almost half the total (11,446 in Aberdare; 13,329 in Merthyr).