Photo caption from published version of 53-4355_007: "SLIT BARN - Built in 1850, the slit barn on M.W. Keefer's Blair estate, on the homestead occupied by W.F. Hussey, is the only one of its kind in Waterloo County. The slits are four inches wide outside and one foot inside. Their purpose is to lessen danger of spontaneous combustion in hay and in the early days of Indian fighting."