Abstract
Although there had been many previous inklings, the field of xenobiotic metabolism (as we know it today) began with an experiment reported in the 1841 literature proclaiming that the ingestion of benzoic acid led to the subsequent excretion of hippuric acid in human urine. A metabolic transformation undertaken by a living organism. One worker involved in the early stages of this discovery was Wilhelm Keller, although very little information about him is readily available. Hopefully, this article will go some way to counter this dearth and also highlight Keller's pioneering contribution in the development of the fields of drug metabolism and xenobiochemistry.