In 1862 the first issue of Trysorfa'r plant (The Children's treasury) appeared, edited by Thomas Levi on behalf of the union of Calvinistic Methodists.  Its circulation was considerable among readers of all denominations.  Each issue contained a variety of material in clear, simple language. By 1881 Trysorfa'r plant sold 40,000 copies a month and over one and a half million copies were sold between 1862 and 1911.