The Man with a Fish on His Back: Science, Romance, and Repugnance in the Selling of Cod-Liver Oil

Early cod-liver advertisement

One of the earliest images of the man with a fish on his back appeared around 1884 on advertising trade cards. Image courtesy of the National Museum of American History Collections, Smithsonian Institution.

The Paper Man

The man stoops forward, glances out from under the brim of his hat, legs braced under the weight of his load. A thick rope, wrapped around his waist, shoulders, and hands, secures the load on his back—a huge fish with gaping mouth and glassy yellow eye, its tail sweeping the ground. A common codfish, the Gadus morhua is recognizable by the brown and amber spots on its body, the light stripe down its side, and the three dorsal fins. The man has few identifying features, but the words “SCOTT’S EMULSION” appear along the hem of his jacket.

By 1900 “the man with the fish” was famous. His image was engraved and embossed on countless boxes and bottles of a cod-liver-oil preparation; printed in full color on advertising trade cards, booklets, and posters distributed around the globe; and in one instance painted several stories high on the side of a building in lower Manhattan. The man with the fish endures today, a testament to the persistence of an age-old tradition, even as scientific and commercial interest in cod-liver oil has waxed and waned.

A “Highly Disagreeable Remedy”

Northern European fishing communities used cod-liver oil for generations to restore health and alleviate aches and pains before the doctors and chemists of 19th-century Europe began to take an interest. Its manufacture was simple: cut out the fish livers (with gallbladders), throw them into barrels, and let them decompose. Fishermen often applied heat to extract the last bits of oil from the smelly, decaying mass. The oil grew darker during the rotting process, resulting in three grades: pale, light brown, and dark brown. “In those days,” wrote pharmacist F. Peckel Möller in his 1895 monograph Cod Liver Oil and Chemistry, “cod-liver oil was not a desirable article of consumption; indeed, to put the matter plainly, it was an abomination, and no one could have taken it willingly, even once, not to speak of day after day and month after month. Nevertheless many people did take it, and the only reasonable explanation is that the oil must have given strikingly favorable results.”

Edinburgh physician John Hughes Bennett played a part in introducing cod-liver oil to the English-speaking medical community. In 1841 he published his Treatise on the Oleum Jecoris Aselli, or Cod Liver Oil, after spending some years in Germany observing its use for the treatment of rickets (a disease marked by soft and deformed bones), rheumatism, gout, and scrofula (a form of tuberculosis). Bennett’s publication quickly spawned further research and experimentation by medical practitioners on both sides of the Atlantic, resulting in the growth of a large cod-liver-oil industry in New England by mid-century.

Ludovicus Josephus de Jongh of the Netherlands produced the first extensive chemical analysis of cod liver in 1843. His studies of the efficacy of the three grades of oil led him to conclude that the light-brown oil was the most therapeutic. He attributed this superiority to the larger quantities of trace substances found in it: iodine, phosphate of chalk, volatile acids, and “elements of bile.”

In 1846 de Jongh traveled to Norway to procure the purest oil available. By the 1850s “Dr.de Jongh’s Light Brown Cod Liver Oil” was marketed throughout Europe and exported to the United States. Each bottle bore de Jongh’s signature and stamped seal—a blue codfish on a red shield—guaranteeing that the product was “put to the test of chemical analysis.” Advertising emphasized de Jongh’s credentials as a physician and chemist and included testimonials from other men of science and medicine. As one 1869 advertisement stated, “It was fitting that the Author of the best analysis and investigations into the properties of this Oil should himself be the Purveyor of this important medicine.”