Rare Pair of CDVs Of Union Cavalry Soldier One is a Dead Letter

Rare Pair of CDVs Of Union Cavalry Soldier One is a Dead Letter. There is a inscription on both CDVS but I have had no luck in Identifiying this Federal Cavalry Trooper. 
 
A dead letter CDV refers to a carte de visite (CDV) photograph of a Civil War soldier that was found in the mail system as "dead letter mail"—it was undeliverable and unreturnable, leading to it being collected by the Dead Letter Office for display or other disposition. These images, popular during the era, were often affixed to a card and sent by soldiers to their families, but many went lost and ended up in the national Dead Letter Office in Richmond, Virginia.