|William Henry Dyer was born in Graig Berthlwyd but spent most of his life near the canal area called the basin but everybody knew him as Mabonwyson “Welsh Poet”. He was reputedly a tall and ugly man and his habits caused him to be kicked out and lived in shack near Garth Cottages. He earned a fair living by writing letters for the people of the Basin and making accounts and wills. He gained admission to the Brecon College for Independents intending to take up the ministry as a livelihood but for some reason was expelled.
Abercynon has produced poets through the centuries who have excelled in village eisteddfodau and penny readings in Welsh and English. The first noted Abercynon who won honours at National Eisteddfods was a former minister the Rev. J.J. Williams (Bethania) who eventually became an arch druid known as J.J. who only lived Abercynon for a short time.