On April 15, 1785, James Jarvis purchased four adjoining lots in Scott's Old Fields, later called Belle Aire, from Aquilla Scott. The lots were numbered 21 through 24 and were each half-an-acre in size and 74 1/4 feet wide. They were along Main Street near the intersection with the road once called the Conowingo or Dublin Road, now known as Pennsylvania Avenue. Scott's plans included lots for a jail and a courthouse to be built on the town's highest land. Although not near a port, major road or center of milling activity, the town was centrally located in Harford County and became the county seat in 1782. In 1799, Belle Aire was described in Scott's Gazetteer as having "an elegant Court House," a Methodist meeting house and businesses including four inns, three stores, blacksmiths, joiners, shoemakers, and wheelwrights.