 Michel's son Christianus Tolkien (1663–1746) was a wealthy miller in Kreuzburg.His son Christian Tolkien (1706–1791) moved from Kreuzburg to nearby Danzig, and his two sons Daniel Gottlieb Tolkien (1747–1813) and Johann (later known as John) Benjamin Tolkien (1752–1819) emigrated to London in the 1770s and became the ancestors of the English family; the younger brother was J. R. R. Tolkien's second great-grandfather.In 1792 John Benjamin Tolkien and William Gravell took over the Erdley Norton manufacture in London, which from then on sold clocks and watches under the name Gravell & Tolkien.