ON INSTRUMENTS FROM ITALY. 121 



or trigger (scatto\ which rests on the above-mentioned higher wheel ; 

 and on the other side he fixed the pendulum, which was made 

 of an iron wire, in which was threaded a ball of lead, which could be 

 loosened by a screw, so that it could be lengthened or shortened ac- 

 cording as it was necessary to regulate it with the weight. When this 

 much had been done Signer Vincenzo wished me (as one who was in 

 the secret of this invention, and who indeed had urged him on to com- 

 plete it), to see, by way of trial, the combined 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 its perpendicular with the 

 longer of the two cords attached to the pivot of the pendulum, it raised 

 the key, which fits into the wheel of the notches ; which wheel drawn 

 by the weight in turning round with its higher parts towards the pen- 

 dulum, pressed with one of its levers on the other shorter cord, and 

 gave it at the beginning of its return such an impulse that it served as 

 a kind of accompaniment to the pendulum, which lifted it 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 key and im- 

 mediately the wheel of the notches was set in motion and continued to 

 revolve and push with the following lever the pendulum, and thus in a 

 certain way, the swinging of the pendulum was rendered continual 

 until the weigh I had reached the ground. We examined together the 

 operation, connected with which, however, many difficulties arose; 

 but Signer Vincenzo did not doubt but that he would be able to over- 

 come all of them ; 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 minutes : for this purpose he set to work to notch 

 (intagliare) another cog-wheel. But whilst engaged in this work, to 

 which he was unaccustomed, he was overtaken by a very acute attack 

 of fever, and he was obliged to leave it unfinished at this point ; and 

 on the twenty-second day of his illness, on the i6th of May, 1649, all 

 his thoughts and aspirations, together with this most exact measurer 

 of time, were lor ever lost to him. He their author passed away to 



