134 SECT10A 7 PHYSICS. 



Tuscan mile=to kil. i '65666, that is to say, it travels at the rate of 

 332 metres per second. 



And at this place, I cannot but call your attention to the fact that 

 it was Prince Leopold who was the life and soul of the Accademia del 

 Cimento. This Macsenas of science facilitated the publication of the 

 most useful and distinguished works, he gave his advice and assistance 

 towards the reprinting of the old works on geometry ; he arranged and 

 watched over the collection of Galileo's works and of the scientific 

 essays of Padre Castelli ; he urged Torricelli to make public the 

 mathematical definitions of inertia ; he encouraged Rinieri to bring 

 to a conclusion the laborious charge, which he had undertaken, of 

 finding the constitution of the Stelle Medicee ; but in 1647 when the 

 latter was giving daily information regarding Jupiter's satellites, and 

 was on the point of publishing the tables, he suddenly died, and his 

 valuable papers were, alas ! very quickly scattered. It was. indeed, a 

 year of ill-omen, for in it Rinieri, Torricelli, and Cavalieri descended, 

 one after another, into the tomb. But their works, the germs of future 

 disciples, outlived them. In fact, ten years afterwards, we find our- 

 selves face to face with a great event in the annals of science, and one 

 most auspicious for Italy, and particularly for Florence namely, the 

 foundation of the first scientific Academy. We are chiefly indebted 

 to Prince Leopold for the great idea of establishing an academy which 

 should be destined expressly to the study of experimental philosophy. 

 That distinguished man, who was accustomed to gather round him 

 for useful conversation the most illustrious persons of his time, thought 

 that researches would be more systematically pursued, and the gather- 

 ings of many men would benefit to a much greater extent the progress 

 of science, if meetings were held regularly and some rules and regu- 

 lations laid down. Ferdinand joyfully agreed to his brother's pro- 

 posal, and showed the greatest generosity towards the new institution ; 

 he presented all his own valuable instruments to it, and even endowed 

 it with the results of his former experiments, several of which have been 

 regarded as the work of the Academy, which was certainly not the 

 case. On the iSth of June, 1657, there was held in the Pitti Palace, 

 the first sitting of the first scientific Academy ; it justly chose to name 

 itself the " Accademia del Cimento" (Attempt, trial, essay), and it 

 selected as its device the now celebrated motto : " Provando e Ripro- 



