XI. TIME. 115 



" working of the weight and the pendulum. I observed the mechanism in. 



" operation more than once, and his workman was likewise present. When 



" the pendulum was at rest it prevented the descent of the weight, but when 



" it was raised and then let go, in passing beyond the perpendicular, Avith 



" the longer of the two arms attached to the pivot of the pendulum, it raised 



" the detent which fits into the scape wheel, which wheel drawn by the weight 



" in rotating with its higher part moving towards the pendulum, pressed with 



" one of its pallets on the other shorter arm, and gave it, at the beginning of 



" its return, an impulse sufficient to cause it to swing to the height from 



" which it had started, so that when it fell back naturally, and had passed 



" the perpendicular, it returned once more to lift the detent, and immediately 



" the scape wheel was set in motion and gave a fresh impulse to the pen- 



" dulum, thus, the swinging of the pendulum was rendered continuous until 



" the weight had reached the ground. We examined the operation together, 



" connected with which, however, many difficulties arose ; but Sig. Vincenzo 



" did not doubt but that he would be able to overcome them all, indeed he 



" fancied that he would be able to apply the pendulum to clocks in a different 



" manner and by means of other inventions ; but since he had got so far, he 



" wished to finish it on this plan, as the drawing shows it, with the addition 



" of hands to show the hours and even the minutes. For this purpose he set 



" to work to cut another cog-wheel. But whilst engaged on this work to which 



"' lie was unaccustomed, he was overtaken by a very acute attack of fever, and 



" was obliged to leave it unfinished at this point, and on the 22nd day of his 



" illness, 011 the 16th of May 1649, all his thoughts and aspirations, together 



" with this most exact measurer of time, were for ever lost to him. He, 

 " their author, passed away to measure (let us hope) in the enjoyment of the 



" Divine Essence, the incomprehensible moments of Eternity." 



Dodecahedron, with eleven solar watches, made in Florence- 

 in 1587. The Royal Institute of u Studii Superiori" Florence. 



Horizontal Solar Watch. 



The Royal Institute of " Studii Superiori" Florence. 



Horizontal Watch, at the latitude of 43 44', made by 

 Cammillo della Volpaja, Florentine, in the second hah 5 of the 16th 

 century. The Royal Institute of " Studii Superiori" Florence. 



Vertical Watch, of boxwood, at the latitude of 43 30' r 

 made in Florence in 1590 by Girolamo della Volpaja. 



The Royal Institute of " Studii Superiori" Florence. 



Night Watch, at the latitude of 43 30', made in Florence in. 

 1568 by Girolamo della Volpaja. 



The Royal Institute of" Studii Superiori" Florence* 



483. Universal Dial, made in 1616 for Prince Charles. 



The Royal United Service Institution. 



Presented to the United Service Museum, in 1832, by Captain W. H. 

 Smyth, R.N., K.F.M., F.K.S., &c., &c. 



485. Universal Dial, in use about 160 years ago. 



The Royal United Service Institution* 



Presented to the United Service Museum in 1838, by His Royal Highness 

 the Duke of Sussex. 



H 2 



