In 1920, Great Britain passed the Seeds Act, which mandated minimum germination and purity standards. Catalogues for farmers such as the Carter’s Tested Seeds Farmer’s Guide and Sutton’s Farmer’s Yearbook both mention this act and show photographs of their seed testing laboratories, as evidence of their willing compliance and rigorous quality control. Catalogues of the 1920s also contain recent innovations such as the delivery of “flowers by wire” and gasoline-powered mowers. Equipment such as greenhouse heating and plumbing equipment is displayed in Chas. Kinnel’s catalogue of 1926. The Joseph Fison company, which pioneered superphosphate fertilizer, stated in its catalogue of 1926 that “the days of plentiful stable and farmyard manure are past and even when supplies of these valuable manures are available, their use in combination with chemical fertilizers is strongly recommended.”