Ancestry.com. Prison diary, of Michael Dougherty, late Co. B, 13th. Pa. Cavalry [database on-line]. Provo, UT: Ancestry.com Operations Inc, 2004.Original data: Dougherty, Michael,. Prison diary, of Michael Dougherty, late Co. B, 13th. Pa. Cavalry : while confined in Pemberton, Barrett's, Libby, Andersonville and other southern prisons : sole survivor of 127 of his regiment captured the same time, 122 dying in Andersonville.. Bristol, Pa.: C.A. Dougherty, printer, 1908.