Tenney was never in the Tenth Kansas. He enlisted as a private in Samuel Stephenson's company of the Third Kansas Volunteers on August 15, 1861, being promoted to regimental Sergeant Major on September 12, 1861, then on January 12, 1861 promoted to First Lieutenant and transferred to the First Kansas Battery. "Roll of the Officers and Enlisted Men of the Third, Fourth, Eighteenth and Nineteenth Kansas Volunteers," pp. 12, 43. His name is found on the rolls of the Tenth Kansas only as that regiment was formed by the consolidation of the Third and Fourth Kansas regiments in April 1862. Seems like I read a history of him somewhere; is his middle name "de Lafayette?"
You can find short histories of the Third and 1st KS Battery at:
http://www.kansasguardmuseum.org/kngunits.html