 Along with Alfred Porter of the same institution, he wrote "An Elementary Treatise on Electricity and Magnetism", founded on Joubert's "Traité Élémentaire D' Électricitié", a standard text in the years around the beginning of the 20th century.Foster was for many years editor of the "Philosophical Magazine", working at this task until shortly before his death.His many achievements were recognised by the granting of honorary doctorates—an LL.D.