Sir John Bennet Lawes invented artificial fertilizer when he discovered superphosphates, his name for the combination of rock phosphate with sulfuric acid. The synthesis of fertilizer had profound implications on agricultural practices, as it freed farmers from absolute dependence on animals to produce manure to feed and nourish their crops. Lawes famously stated that his discovery of synthetic fertilizer established that agriculture can be an artificial process, or one that is not completely bound to the vagaries of nature. In the practical realm, his discovery led to the establishment of the fertilizer industry, which became an important segment; in the scientific realm, Lawes collaborated with Sir Joseph Henry Gilbert to found the Rothamsted Experimental Station (RES), where the pair performed their "classical experiments" on the effects of artificial fertilizers on soil conditions and crop yields.
John Bennet Lawes was born on December 28, 1814, at Harpenden, in Hertfordshire, England. His father owned the Rothamsted estate, which Lawes inherited in 1822. After several unsuccessful attempts at obtaining a university education (studying at University College, London under A. T. Thomson, at Eton College, and at Oxford’s Brasenose College), Lawes returned to farm the family manor in 1834.
Over the next eight years, Lawes experimented with both organic and inorganic fertilizers. Traditionally, farmers fertilize with manure, thus making them dependent on animals to produce this natural fertilizer. Seeking to free farmers from this dependence, Lawes experimented with the use of ground-up animal bones, which proved to be an excellent fertilizer. He subsequently discovered that sulfuric acid, a cheap byproduct of many industrial applications, could perform the same function as grinding at much less expense. His next innovation was to substitute rock phosphate, derived from the petrified residues of bird excreta, for the animal bone, which had the same limiting effects as manure.
In 1842, Lawes patented his phosphate-sul-furic acid mixture as "superphosphate," the first artificial fertilizer. Within the next year, he had established a superphosphates manufacturing facility in Deptford, importing Chilean nitrates for the necessary nitrogen content, and he later founded the Lawes Chemical Company Ltd., which manufactured other agricultural chemicals in addition to superphosphates. Lawes thus founded the artificial fertilizer industry, a segment that would have profound effects upon the future of agriculture.
Also in 1843, Lawes commenced his collaboration with Joseph Henry Gilbert, who he appointed as the chemist at Rothamsted Laboratory, as he dubbed his manor, as the first agricultural experimental station in the world. Lawes and Gilbert continued their partnership over the next 57 years at what came to be known as the Rothamsted Experimental Station, which continues to this day the research that Lawes and Gilbert initiated.
Lawes and Gilbert commenced nine long-term experiments that became known as the Rothamsted Classical Experiments (one project was abandoned in 1878, leaving eight ongoing experiments). Lawes and Gilbert endeavored to track the effects on crop yields of the elements known to be contained in manure—namely, nitrogen, phosphorous, potassium, sodium, and magnesium. The experiments compared trial plots fed different combinations and concentrations of these minerals with plots fertilized with manure. Lawes conscientiously recorded the weight of the produce yielded by each crop for future comparison, and Gilbert sampled the soil for chemical analysis. Their efforts held practical implications for farmers, who fertilized their crops according to the results reported from the RES.
Lawes gained recognition for his pioneering efforts, as the Royal Society inducted him into its fellowship in 1854 and awarded him and Gilbert its royal medal in 1867. In 1878, he became a fellow of the Institute of Chemistry, and in 1882, the title of baronet was bestowed on him. The Royal Society of Arts awarded him its 1894 Albert medal, and Lawes received honorary degrees from Cambridge, Oxford, and Edinburgh Universities, representing quite a distinction for a man who never earned a university degree on his own.
Lawes died on August 31, 1900, at the Rothamsted manor. More than a decade before this, though, in 1889, he established the Lawes Agricultural Trust to fund the ongoing efforts of the Rothamsted Experimental Station and to support the continuation of the classical experiments, which continued after his death with very few modifications.