The Cunard S.S. Co. (D) had the custom of providing smallpox vaccinations on board ship to avoid quarantine problems when their passengers arrived in the U.S. Notice of quarantine regulations and the willingness to give passengers vaccinations was posted throughout the ship in various languages. About 200 women passengers were assembled and were vaccinated. O'Brien (P) stood in a line of women who waited to have the injections and saw the entire process of examination and vaccination. When D's turn came up, she showed her arm and told the doctor that she had been vaccinated before, but it had left no mark. D said nothing about not wanting to be vaccinated again. The doctor did not reply but told her to get vaccinated again whereupon she raised her arm and received the shot. The ship's doctor assumed that P consented to receiving the vaccination because there was nothing in her conduct to indicate the contrary. P sued D for vaccinating her against her will. The verdict was directed to D, and P appealed.