Ida Tarbell grew up in the Pennsylvania oil fields of the 1860s, surrounded by gushing wells, deadly explosions, and the wreckage left by the South Improvement Company, a secret alliance of railroads and oil interests that crushed independent refiners like her father in 1872. This episode follows how that childhood, a biology education at Allegheny College, and archival training in Paris produced a new kind of reporter, one who treated her subjects the way a scientist treats a specimen.

At McClure’s Magazine she first applied the method to Napoleon and Abraham Lincoln, tracking down people who had known Lincoln and unearthing more than 300 unknown letters and speeches. Then she turned it on John D. Rockefeller. Her 19 part history of the Standard Oil Company relied on documents rather than outrage, and it helped bring about the Hepburn Act, the Federal Trade Commission, and the Supreme Court breakup of the monopoly. The episode also weighs her puzzling opposition to women’s suffrage.

• After the Panic of 1857 wiped out the family’s savings, her father walked back to Pennsylvania from Iowa over 18 months, arriving in rags. Young Ida told him to go away.
• At The Chautauquan she went to the U.S. Patent Office to check a claim that only about 300 women held patents, and found close to 2,000.
• Publisher Sam McClure recruited her in Paris, missed his train, and had to borrow 40 dollars she had saved for a vacation.
• A Standard Oil office boy assigned to burn records noticed his Sunday school teacher’s name on them. The documents, showing the company still got advance word of rivals’ shipments from railroads, reached Tarbell.
• Theodore Roosevelt labeled her and her colleagues muckrakers, a name she despised because she believed facts, not attacks, change minds.