...clock worked by water. The dial was composed of twelve small doors, which represented the division of the hours ; each door opened at the hour it was...and marching round the dial, shut all the doors." By this time the Romans had learned to make sounding clepsydrae ; and later still, Lucian describes...

...of twelve small doors representing the divisions of the hours ; each door opened at the hour it wai intended to represent, and out of it came the same...horsemen in miniature issued forth at the same time, and, inarching round the dial, shut all the doors. Hour-glasses, called clepsammia, in which sand took the...

...number of doors that were open ; and by the ear, by the number of balls that fell. When it was twelw o'clock, twelve horsemen in miniature issued forth...time, and marching round the dial shut all the doors." Old St. Paul's was not without a curiosity of this character; for, according to Dugdale's history of...

...balls, which fell one by one, at equal distances of time, on a brass drum. ' By the eye it might be told what hour it was by the number of doors that were...and, marching round the dial, shut all the doors.' 85. The Hour-glass. — Soon after the introduction of waterclocks another form of measuring time was...

...their hands is not certain. Improvements must have been made somewhere, for early in the Middle Aces we find clepsydras in forms more highly developed...as an object of study, is the medieval clepsydra. This looks more than ever like the clock we are accustomed to see. It has weights as well as wheels....

...from the King of Persia. " The dial was composed of twelve small doors, which represented the division of the hours ; each door opened at the hour it was...and marching round the dial, shut all the doors." One of the earliest epochs, perhaps the very earliest in the history of horological machinery, is marked...