Edit - While Col. Clark's name appears at the very beginning of the text of this lengthy history, the quote in question comes from page 20 of the appendix, which identifies the colonel as Col. Cillie (Cilley).
Colonel Jonathan P. Cilley, Commander, First Maine Cavalry and Brigadier General Charles H. Smith, Commander, Third Brigade, Second Division, Cavalry Corps. Source
Howard Aston, History and Roster of the Fourth and Fifth Independent Battalions and Thirteenth Regiment Ohio Cavalry Volunteers. (Columbus, OH: Fred J. Heer, 1902), Appendix p. 20.
Edit - As was pointed out, the question did not ask for first names, so answers giving only the correct last names of the two officers were accepted.
Alternative spellings of the colonel's name were accepted, as long as they were reasonably close.