autochronograph

From auto- +‎ chronograph.

autochronograph (plural autochronographs)

1. (rare, archaic) An instrument for the instantaneous self-recording or printing of time.

• Edward H[enry] Knight (1877) “Autochronograph”, in Knight’s American Mechanical Dictionary. […], volumes I (A–GAS), New York, N.Y.: Hurd and Houghton […], →OCLC.
• “autochronograph”, in Webster’s Revised Unabridged Dictionary, Springfield, Mass.: G. & C. Merriam, 1913, →OCLC.