All his life he was interested in the Welsh language and in music. He contributed many articles to such periodicals as Y Gwyliedydd , Seren Gomer , and Cymro Llundain under the pseudonyms T. ap Edwart ap Eurgain , Zabulonun , and Caerfallwch . Y Gwyliedydd , 1829-30 , published one of his lectures on minerals, etc., ‘delivered in the presence of the Society of Cymreigyddion in London on Thursday night, the 1st July, 1830 .’ He wrote poetry after the manner of Pughe (see two lyrics in Ceinion Awen y Cymry , 121-4). Airs composed by him are to be found, for example, in Seren Gomer , v, 224, and vi, 64. But his principal efforts were directed to enriching the Welsh language by the devising of new words to express new technical developments , more especially in science. In 1845 he published his Analysis of Welsh Orthography in which the language is dissected in Pughe 's way, consonantal mutations and vowel changes are described, and the use and meaning of prefixes and suffixes are explained. This was republished in his magnum opus , Geirlyfr Saesoneg a Chymraeg, An English and Welsh Dictionary ( Holywell , printed and published by P. M. Evans , 1850 ). In this dictionary will be found a host of words invented by himself to correspond to new English words appearing in the various spheres of knowledge. Now, a century after his death, committees are engaged in trying to do the same thing. Incidentally, it would appear that Caerfallwch himself invented the Welsh word for committee — pwyllgor (from pwyll , deliberation, and cor , assembly, company).
Caerfallwch was one of the members of Jewin Welsh Methodist church , London , excommunicated by the Calvinistic Methodist authorities for supporting the emancipation of Roman Catholics .
Emeritus Professor Henry Lewis, D.Litt., (1899-1968), Swansea
Published date: 1959