In the eighteen hundreds, Fairfax County was a rural agricultural society, and at Walney the barnyard was the center of farm activity. Walney’s three-story barn, which once stood across the road, was built of fieldstone rather than the more common wood timber frame, because stone was plentiful on the property and more durable. Horses and cows grazed in the cattle yards and stables, while enslaved African American and hired white workers gathered supplies from the sheds to labor in the fields. The Machens kept the animals and tools needed to operate the farm there, and according to the 1850 agricultural census of Fairfax County, Lewis Machen owned 5 milk cows, 49 cattle, 150 sheep, and 11 horses. These animals provided food, supplies, and income. The dairy stood near the spring so water could keep milk, cheese, and butter cold and fresh. Cows were milked twice a day in the barnyard, and the milk was carried to the dairy for processing and storage. In 1879, James P. Machen hired Tobe Horton for a year to milk half of his cows night and morning, bring them into the cow pen or stable yard for milking, clean manure daily from the stable when occupied, and wash and thoroughly cleanse the milk vessels and cans after each milking.