Known as "Dutch cocoa", this machine-pressed chocolate was instrumental in the transformation of chocolate to its solid form when, in 1847, English chocolatier Joseph Fry discovered a way to make chocolate moldable when he mixed the ingredients of cocoa powder and sugar with melted cocoa butter. Subsequently, his chocolate factory, Fry's of Bristol, England, began mass-producing chocolate bars, Fry's Chocolate Cream, launched in 1866, and they became very popular. Milk had sometimes been used as an addition to chocolate beverages since the mid-17th century, but in 1875 Swiss chocolatier Daniel Peter invented milk chocolate by mixing a powdered milk developed by Henri Nestlé with the liquor. In 1879, the texture and taste of chocolate was further improved when Rudolphe Lindt invented the conching machine.