The publication of Upton Sinclair's 1906 novel The Jungle produced an immediate and powerful effect on Americans and on federal policy, but Sinclair had hoped to achieve a very different result. At the time he began working on the novel, he had completed his studies at Columbia University and was trying to develop a career as an author. He had been born in Baltimore in 1878, but his family had moved to the Bronx in 1888. Though he came from a prominent family, his own parents had little money, and he paid for his university studies by writing dime novels and short stories. While at Columbia, he also became a convert to socialism.

At the time, journalists had begun to play an important role in exposing wrong doing. Around 1902, magazine publishers discovered that their sales soared when they featured exposés of political corruption, corporate misconduct, or other offenses. McClure's Magazine led the way, in October 1902, with a series by Lincoln Steffens that revealed corruption in city governments. In January 1903, McClure's carried Steffens's installment on Minneapolis, launched a new series by Ida Tarbell on Standard Oil, and featured an article on corruption in labor unions. McClure's sales boomed, and other publications quickly commissioned exposés of their own.

In 1904, the leading socialist weekly in the country, The Appeal to Reason, offered Sinclair $500 (equivalent to about $11,500 in 2008) to prepare an exposé on the meatpacking industry. Upon arriving in his hotel in Chicago, Sinclair is said to have announced, "I am Upton Sinclair, and I have come to write the Uncle Tom's Cabin of the labor movement." For seven weeks, he prowled the streets of Packingtown, the residential district next to the stockyards and packing plants. He donned overalls, posed as a worker, and slipped into the packing plants to gain first-hand knowledge of the work. He sought out social workers, police officers, physicians, and others who could tell him about life and work in Packingtown. Local socialists introduced him to other people who were knowledgeable about the community and the work. At the end of seven weeks, he returned home to New Jersey, shut himself up in a small cabin, and wrote for nine months.

The book he produced, The Jungle, followed a fictional family of Lithuanian immigrants in Chicago. From an opening chapter that recounts the joyous wedding of the main character, Jurgis Rudkus, Sinclair traced the family's experience with work in Packingtown. In the process, he exposed in disgusting detail the inner workings of the meatpacking industry:

They were regular alchemists at Durham's; they advertised a mushroom-catsup, and the men who made it did not know what a mushroom looked like. They advertised 'potted chicken' . . . the things that went into the mixture were tripe, and the fat of pork, and beef suet, and hearts of beef, and finally the waste ends of veal, when they had any. They put these up in several grades, and sold them at several prices; but the contents of the cans all came out of the same hopper. And then there was 'potted game' and 'potted grouse,' 'potted ham,' and 'deviled ham'--de-vyled, as the men called it. 'De-vyled' ham was made out of the waste ends of smoked beef that were too small to be sliced by the machines; and also tripe, dyed with chemicals so that it would not show white; and trimmings of hams and corned beef; and potatoes, skins and all; and finally the hard cartilaginous gullets of beef, after the tongues had been cut out. All this ingenious mixture was ground up and flavored with spices to make it taste like something.

Sinclair described the afflictions of packinghouse workers, from severed fingers to tuberculosis and blood poisoning. He wrote of men who "fell into the vats; and when they were fished out, there was never enough left of them to be worth exhibiting--sometimes they would be overlooked for days, till all but the bones of them had gone out to the world as Durham's Pure Leaf Lard!" And he told of scheming real estate salemen and crooked politicians.

At the center of the story, Sinclair recounts the destruction of Jurgis's family because of the corrupt, exploitative, and oppressive nature of work and life in Packingtown. Finally Jurgis is left alone, stripped of all dignity. One evening, he wanders into a meeting hall to escape the cold, hears a speech on socialism, and becomes an ardent convert to that cause. The final section of the novel features arguments for socialism, in the form of speeches that Jurgis hears. The book ends with a socialist orator's impassioned appeal to "Organize! Organize! Organize!" so that "Chicago will be ours! Chicago will be ours! CHICAGO WILL BE OURS!"

Sinclair's work broke with the mold established by previous exposés in two ways. First, his was a work of fiction that followed one family over a period of years and, in the process, detailed unsanitary food preparation, exploitation of workers, sleazy real-estate practices, political corruption, and much more. Second, where many previous authors had suggested that the reform of the abuses they described could be accomplished by the election of honest men, Sinclair had a larger goal: the rejection of capitalism and the victory of socialism. He intended that his readers would recognize that the horrors portrayed in his book were the result of corporate greed and exploitation and that the meatpacking industry was but a microcosm of capitalism—that the jungle was actually industrial capitalism. In the serialized version, he states: "the place which is here called The Jungle is not Packingtown, nor is it Chicago, nor is it Illinois, nor is it the United States—it is Civilization."

In late February 1905, the Appeal to Reason began to publish Sinclair's work as a serial, one chapter per week, and the paper's sales boomed to 175,000 per issue. Between April and October, the complete version also appeared in four installments in a small, socialist, quarterly magazine called One-Hoss Philosophy. The novel drew praise from prominent Socialists, including the best-selling novelist Jack London. But Sinclair wanted his work to reach the widest possible audience. Just as Steffens's and Tarbell's works had appeared as books, so Sinclair intended his novel to be a book. He first approached Macmillan, the publisher of his previous novel, a Civil War story called Manassas. Though initially interested, Macmillan eventually backed off. According to Sinclair, five other publishers did the same. As he went to publisher after publisher, he was also revising the version that had appeared in serial form, trimming it, removing duplicative material, modifying the final chapters, improving his use of Lithuanian phrases, and modifying material that might have invited a lawsuit for libel. Discouraged about finding a publisher, he finally asked the readers of The Appeal to Reason to contribute funds to enable him to publish it himself. Just as he was about to begin his self-publishing venture, he received an acceptance from Doubleday, Page and Company.

Like other publishers, Doubleday had been concerned for the possibility of legal liability if the packing companies were to sue. Their offer to publish was contingent on their ability to verify the truth of Sinclair's descriptions of the packing plants. One of their editors went to Chicago and interviewed a former governmental meat inspector, who confirmed that Sinclair's version was not exaggerated. Not satisfied, the editor secured an inspector's badge and prowled through the vast packing plants. His conclusion: things were as bad as Sinclair had reported, maybe worse. The book was released on January 25, 1906, and created an international sensation, selling 25,000 copies in six weeks. It has never been out of print and was made into a movie in 1913.

The stir created by The Jungle quickly reached all the way to the White House. The nation's leading political humorist, Finley Peter Dunne, who wrote in the character of a Chicago saloonkeeper named Mr. Dooley, imagined the reaction of President Theodore Roosevelt:

Tiddy was toying with a light breakfast an' idly turnin' over th' pages iv th' new book with both hands. Suddenly he rose fr'm th' table, an' cryin': 'I'm pizened,' began throwin' sausages out iv th' window. . . . Since thin th' Prisidint, like th' rest iv us, has become a viggytaryan.

In fact, Roosevelt behaved quite differently. His first reaction was to consult with the Agriculture Department, which reported that meatpacking was carefully inspected and meat was safe to eat. Roosevelt then wrote to Frank Doubleday, berating him for publishing "such an obnoxious book." Doubleday replied that his company had confirmed Sinclair's descriptions. Roosevelt launched his own investigation, which confirmed, in Roosevelt's words, that "the method of handling and preparing food products is uncleanly and dangerous to health," but he announced only that he had the report and did not release its contents.

Congress at the time was considering a pure-food-and-drug bill, the result of a series of earlier exposés of patent medicines and impure foods as well as continued lobbying by Harvey Wiley of the Bureau of Chemistry in the Agriculture Department and pressure from such groups as the American Medical Association. Roosevelt himself, in his 1905 message to Congress, had recommended action on the subject. However, conservative opposition to any regulation combined with opposition from drug and food-processing companies seemed likely to defeat the bill. The public outcry created by The Jungle changed the dynamic in Congress. The Senate approved the pure-food-and-drugs bill in late February by a vote of 63-4. However, the pure-food-and-drugs bill included no provision for meat inspection. Accordingly, Senator Albert Beveridge of Indiana, a progressive Republican, proposed legislation requiring federal inspection of all meat that moved in interstate commerce and directing the Department of Agriculture to regulate conditions in the packinghouses. Beveridge described his bill as "the most pronounced extension of federal power in every direction ever enacted." Roosevelt, still withholding his report, threatened to release it unless the Senate took action on Beveridge's bill. The Senate approved the bill.

The meat packers now joined other food processing companies in focusing on the House of Representatives, where both bills now lay. When powerful House members sought to dilute the Beveridge bill, Roosevelt released the report, which, he proclaimed, clearly demonstrated that conditions in the stockyards were "revolting." The strategy did not work. Opposition continued. Finally a compromise emerged—Beveridge's bill had provided that a fee would be assessed on every animal slaughtered, to pay for the inspection and regulation, but the compromise specified that the costs would be borne by the federal government; Beveridge had wanted a date to be stamped on all canned meat, but the compromise omitted any requirement for dating. Nonetheless, Beveridge and Roosevelt agreed that the compromise was better than no regulation at all. Roosevelt signed both the Meat Inspection Act and the Pure Food and Drug Act into law on June 30, 1906. He described those two laws, together with a bill to regulate railroad rates, as marking "a noteworthy advance in the policy of securing Federal supervision and control over corporations." Historians have agreed with Roosevelt's analysis, citing the three bills passed in 1906 as major early steps in the development of federal regulation of a wide range of economic activity.

Though less than six months had passed from Doubleday's publication of The Jungle to the signing of the Meat Inspection Act, Sinclair was disappointed that his book had produced only a federal law regulating meatpackers and not a surge of popular support for socialism. "I aimed at the public's heart," he famously observed, "and by accident I hit it in the stomach." Though the book failed to create a surge of converts to socialism, it was very good for Upton Sinclair, who now, at the age of twenty-eight, catapulted into international prominence. Sinclair's career as an author was both long and productive. By the time of his death in 1968, he had written more than ninety books, with translations into nearly fifty languages, and had won a Pulitzer Prize. He had dabbled in politics as a Socialist until 1934, when he changed his party registration and won the Democratic nomination for governor of California. His campaign was based on a program he called EPIC (End Poverty in California), but he lost when his Republican opponent mounted a highly sophisticated, media-based negative campaign that some scholars have seen as the origins of modern media-driven campaigns.

Theodore Roosevelt remained unhappy with the constant journalistic exposés. In the midst of the controversy over meatpacking, on April 14, 1906, he gave a speech that has become known as "The Man with the Muck-Rake." In that speech, he discussed journalists who specialized in exposés:

In Bunyan’s “Pilgrim’s Progress” you may recall the description of the Man with the Muck-rake, the man who could look no way but downward, with the muck-rake [manure rake] in his hand; who was offered a celestial crown for his muck-rake, but who would neither look up nor regard the crown he was offered, but continued to rake to himself the filth of the floor.

In “Pilgrim’s Progress” the Man with the Muck-rake is set forth as the example of him whose vision is fixed on carnal instead of on spiritual things. Yet he also typifies the man who in this life consistently refuses to see aught that is lofty, and fixes his eyes with solemn intentness only on that which is vile and debasing.

Robert W. Cherny is professor of history at San Francisco State University. He is the author of several books and articles on American politics, 1865-1940, including American Politics in the Gilded Age, 1868-1900; A Righteous Cause: The Life of William Jennings Bryan; and San Francisco, 1865-1932, with William Issel. He is also co-author of two textbooks: Making America and Competing Visions: A History of California.