B&O No. 8 "John Hancock"
The "John Hancock" was built in April of 1836 by Ross Winans and George Gillingham at the Mt. Clare shops. This was one of a series of enhanced "Grasshoppers", which introduced a number of improvements such as a covered cab for the engineer and dual-powered axles. As the first B&O locomotive with a cab, the "John Hancock" weighed twice the amount of the original "Atlantic." Later transferred to switching service, the "John Hancock" was in continuous operation at Mt. Clare from 1836 until 1892.
During the 1850s, the B&O ceased naming individual locomotives and began using only numbers to designate locomotives. The No. 8 "John Hancock" was stripped of its name and left with only the No. 8. In the renumbering program of 1884, the No. 8 was renumbered as the No. 3, as the third oldest B&O locomotives in existence. It was one of four "Grasshoppers" that survived until 1892 when it retired from service and sent to the World's Columbian Exposition in Chicago. At that time, No. 3 was incorrectly named the "Thomas Jefferson," which had been the original No. 3 "Grasshopper" locomotive. --from the B&O Railroad Museum's web site.