Note 182 — Terminal Essay.

Time-measurers are of very ancient date. The Greeks had clepsydræ and the Romans gnomons, portable and ring-shaped, besides large standing town-dials as at Aquileja and San Sabba near Trieste. The “Saracens” were the perfecters of the clepsydra: Bosseret (p. 16) and the Chronicon Turense (Beckmann ii. 340 et seq.) describe the water-clock sent by Al-Rashid to Karl the Great as a kind of “cuckoo-clock.” Twelve doors in the dial opened successively and little balls dropping on brazen bells told the hour: at noon a dozen mounted knights paraded the face and closed the portals. Trithonius mentions an horologium presented in A.D. 1232 by Al-Malik al-Kámil the Ayyubite Soldan to the Emperor Frederick II: like the Strasbourg and Padua clocks it struck the hours, told the day, month and year, showed the phases of the moon, and registered the position of the sun and the planets. Towards the end of the fifteenth century Gaspar Visconti mentions in a sonnet the watch proper (certi orologii piccioli e portativi); and the “animated eggs” of Nurembourg became famous. The earliest English watch (Sir Ashton Lever’s) dates from 1541: and in 1544 the portable chronometer became common in France.