Hemingway’s novel, The Old Man and the Sea, opens with a scene of fishermen preparing their catch for market in a Cuban port. “Those who had caught sharks,” Hemingway writes, “had taken them to the shark factory on the other side of the cove.” Here the sharks were “hoisted on a block and tackle, their livers removed, their fins cut off and their hides skinned out.” Shark hide, referred to as “shark leather” in its processed form, was likely unfamiliar to most American readers when Hemingway’s novel appeared in 1952. Yet, for a brief period of time, during the 1920s, the shark leather industry had attracted a great deal of public interest. The prospect of turning sharks into leather seemed then to promise a valuable untapped marine industry, made possible though the collaboration of chemists, fishermen, and entrepreneurs.

One of the first people to try to develop the shark leather industry was a Czech emigrant to the United States named Alfred Ehrenreich. As The Milwaukee Journal announced in January 1928, “Since the beginning of time, when man first ventured on the sea, the shark has been man’s enemy.” Ehrenreich, the author announced, was “going to make the shark work for man.” Ehrenreich arrived in the United States in 1914, fleeing the outbreak of war in Europe. As a young man he had studied in Vienna and worked in the banking industry. He had spent his vacations, however, yachting on the Adriatic and Mediterranean, and there became fascinated with the biology of sharks. Soon he turned all his energies to developing commercial uses for sharks, rays, and porpoises. His first success was his discovery of a method for extracting oil from shark livers, but the real breakthrough came when he learned about the work of Brodo Bendixon, a chemist working in Copenhagen who had then recently patented a technique for tanning shark skins.

In 1917 Ehrenreich and Bendixon, with backing from American investors, launched the Ocean Leather Company in the United States and opened a small experimental tannery in Newark, New Jersey. Yet despite several years of continuous experimentation, the key process for turning sharkskin into a marketable-quality leather remained elusive. In a letter to investors, Ehrenreich explained that they had been unable to remove the “dermal dentical upon the skin of the shark” which was “hard as steel,” despite trying both mechanical and chemical techniques. A solution was finally discovered in 1919 thanks to the research of American chemists Theodore Kohler and Allen Rogers, both of whom had developed tanning methods using hydrochloric acid.

Ehrenreich eventually hoped to produce much more than just leather from sharks. By 1920, the Ocean Leather Company had developed techniques for transforming the entire shark into various commodities: leather from the hide and intestine, oil from the liver, tanning chemicals from the glands, pigments from the gall bladder, fertilizer from the refuse, and fins and meat for the Asian food market. With the tanning process perfected, Ehrenreich now needed a steady supply of sharks and consumers. By 1920 the Ocean Leather Company announced to shareholders that they planned to increase catch to 1000 sharks a day and predicted a daily net profit of $17,076. Indeed, by 1921 the New Jersey tannery was processing nearly a thousand skins per week. The processed leather was then sold to manufacturers to make handbags and shoes.

 

At the height of their profits in the late 1920s, the Ocean Leather Company enjoyed endorsements from Teddy Roosevelt, Thomas Edison, Henry Ford, and the Department of Commerce. Flush with cash they purchased a yacht named the Istar, and fitted her out as a floating factory and laboratory. A  description of the Istar appears in Milwaukee Journal:

The other day I paid a visit to the Istar, lying in the East India docks, […] It is now the only floating factory, tannery and chemical works in the world. I was shown a luxurious dining room and sumptuous bedrooms whose walls were lined with silk brocade. And from those rooms – bang into a factory with whirling machinery. […] It carries 10 motorboats, each equipped with 15 horsepower Diesel engines. Each boat is capable of holding five tons of sharks […] When the haul is made, the sharks are brought back to the ship. Here an ingenious machine invented by Ehrenreich skins the hide off as easily as you would peel a banana. The hide is then immediately salted down and treated with chemicals.

With the Istar, the Ocean Leather Company could expand its reach into the Southern Ocean where the number of sharks was thought “endless” and where the Istar could harvest a catch of thirty tons a day. Though the Istar garnered publicity for the company and carried out several successful hunting expeditions to Australian waters, it was not enough to guarantee the long-term success of the company. Ehrenreich found he had powerful enemies in the cow leather industry. One of his collaborators, Viennese chemist Rudolf Hauschka, who was in charge of outfitting the Istar, later described receiving death threats. “The world’s leather manufacturers went into the attack […] finally, I came to the realization that in a battle with a well organized world power we were bound to come off worst,” he wrote.

 

While the history of the shark leather industry (and of many other marine products) remains understudied, it nevertheless points us to a key feature of the history of science in the marine environment, often overlooked by historians. What the history of the shark leather industry shows us is that we should pay attention to the scientific work involved in “processing”marine products – the work of turning marine fauna into valuable commodities.

Additional reading:

José I. Castro, “Historical Knowledge of Sharks: Ancient Science, Earliest American Encounters, and American Science, Fisheries, and Utilization,” Marine Fisheries Review, (75) 4 (2013), pp. 1 -26.

Rudolf Hauschka, Dawn of a New Age: Memoirs of a Scientist (Frankfurt: Vittorio Klostermann, 1966).