age ~82
from New Philadelphia, OH
where she lived near the IRT Sixth Avenue Line.
The rights to her invention, patented in 1881, were sold to the Metropolitan Railroad for $10, 000 and the system was soon adopted by other elevated railway companies.
Inventor
Mary Walton was an American independent inventor who worked in the late 19th century. In 1879, Walton created a method for reducing the environmental ...