David Erwyd Jenkins, 1911 Encyclopædia Britannica, Volume 5… (1911)
“ His first Sunday School was in 1787. Wilberforce, Charles Grant, John Thornton and his son Henry, were among the philanthropists who contributed to his funds; in 1798 the Sunday School Society (established 1785) extended its operations to Wales, making him its agent, and Sunday Schools grew rapidly in number and favour. A powerful revival broke out at Bala in the autumn of 1791, and his account of it in letters to correspondents, sent without his knowledge to magazines, kindled a similar fire at Huntly. The scarcity of Welsh bibles was Charles’s greatest difficulty in his work. ”
