Bell's flour business was in Bath Lane, Newcastle. Two of his best-selling products were baking soda and self-raising flour, marketed as 'Bell's Royal', at the turn of the century. As it was illegal to use the word 'royal' commercially in the reign of Edward VII, Bell changed the product's name to 'Be-Ro'. In the early 1920s, self-raising flour was a novelty. Exhibitions were widely held, where freshly-baked scones, pastries and cakes were sold for a shilling to visitors. Demand for recipes was so great that the first Be-Ro book was produced in 1923, containing 19 pages. It has now grown to 86 pages and has reached its 40th edition. With sales of over 38 million it has claims to be the best-selling English cookery book of all time.