Hmmm. Thats Battery C, 6th US Colored Heavy Artillery. Which likely means he was either 1st lieutenant or 2nd lieutenant…. Formed Vicksburg Mississippi Marck/April 1864. It was never at Leavenworth. Which means he also would have been in an earlier unit, maybe a Kansas one, in 1862-1863 prior to taking a medical discharge for the typhoid in late 1863.