Illustrated Companion to the Latin Dictionary/Horologium

This article incorporates text from a publication now in the public domain: Rich, Anthony (1849). The illustrated companion to the Latin dictionary, and Greek lexicon. p. vi. OCLC 894670115. https://archive.org/details/illustratedcompa00rich. 

HOROLOG'IUM (ὡρολόγιον). An hour-measure, or horologe; a general term employed for any contrivance which marked the lapse of time, whether by day or night, and without reference to the agent employed; consequently, including the various kinds of sun-dials (solaria), and water-glasses (clepsydrae), which are enumerated in the Classed Index. Our term clock conveys an improper notion of the ancient horologium; for the only instruments known to the ancients for performing the duties of a modern clock, were water-glasses and sun-dials.