Nominated 27 June 1913 as 'late midshipman, United States Navy' to be second lieutenant of Field Artillery, with rank from 26 June 1913 (H-C01). Page as printed.
Image · dated 27 Jun 1913 · source: Internet Archive (public-domain scan); sim_congressional-record-proceedings-and-debates_june-17-1913-august-2-1913_50

How it is shown: Complete page image as saved; no crop, no retouch.
Keep in mind: Confirmed as printed (H-C0x). The page lists many officers; only Herbert Slayden Clarkson is tagged. Printed list, not proof of his service.
Evidence for
- Congressional Record (Senate), 27 Jun 1913, p. 2238: nominations received, appointment in the Army, Field Artillery Arm · the original at U.S. Congress, Congressional Record (Internet Archive scan)