Mary Hallman was born in either 1824 or 1825. She was married to George Hallman who predeceased her. She also had at least one daughter who later married a gentleman from Norristown named William Baird. By 1895 at the age of 70 , Mary Hallman was residing in Plymouth Township. On May 26, 1895, she was a passenger of a Trolley running on the Norristown & Chestnut Hill Line.
As the Trolley neared the intersection of Hallowell Avenue and Germantown Pike, the trolley suddenly lurched and caused her to lose her balance. As a result, Mary was thrown from the trolley and suffered a broken left arm, bruising to her left shoulder, and cuts and bruising to her face. In addition, the accident caused her to develop brain fever, or swelling in her brain. Taken to Charity Hospital, she hovered between life and death for nearly six weeks before the swelling took her life on July 2, 1895.