Union medical officer. Original 2.5 x 4 carte-de-visite portrait by Barnett’s of New York, signed and inscribed on the reverse in black ink, “Aug. 20, 1863, Your affectionate Brother, Wm. T. Cross, ex surgeon’s steward, U. S. N., To S. T. Chamberlin.” In fine condition, with scattered speckling to image. RR Auction COA.