My great-great-great uncle served in the 13th Illinois Regimental Volunteer Cavalry from 1861-1865. He mustered in at Camp Douglas in 1861 and served in Co. A as well as the Consolidated Cavalry. A very nice write-up of the activities of the 13th Illinois Cavalry was written by Major Frederick Behlendorff after the war. I obtained a copy via microfiche at the War Library in Carlisle, PA a few years ago. It is probably the most comprehensive summary of the units acitivities during the war.