Memoir of the Life and Writings of M. Piazzi. 197 



The illness, which we have already mentioned, continued for 

 nearly four years to interrupt the observations of our author, 

 but he still wrought with the same zeal ; and having conceiv- 

 ed the plan of re-examining the thirty-six stars of Maskelyne, 

 he engaged his assistant, M. Cacciatore, to undertake this dif- 

 ficult task. 



These observations were made upon 120 stars, which form- 

 ed the basis of a new catalogue, which contained no fewer than 

 7646, and was published in 1814. 



At the urgent request of his friends and his pupils, Piazzi 

 now devoted his time to the composition of several memoirs, 

 destined for the different academies of which he was a member. 

 The Neapolitan Government had entrusted him with the reno- 

 vation of the system of weights and measures in Sicily, and 

 after completing this task he published, in 1808, an essay on 

 the subject, intended to instruct the clergy in the new system. 



During the Constitutional Government of 1812, Piazzi was 

 consulted on the subject of a new territorial division of Sicily, 

 which, decreed by parliament, according to a report of our 

 author, was preserved even after the destruction of the repre- 

 sentative government. 



The great comet of 1811, which excited such general no- 

 tice throughout Europe, gave our author an opportunity to 

 publish his opinions on the nature of these bodies. He sup- 

 posed that they were not formed contemporaneously with the 

 planets, but that they were produced from time to time in the 

 immensity of space, where they afterwards dissipated them- 

 selves like those globes of fire and luminous meteors which 

 have their origin and disappear in our own atmosphere. 



In the year 1817 Murat, King of Naples, founded a new 

 observatory on the heights of Capo di Monte, and M. Piazzi 

 was invited to Naples to examine it. He introduced many 

 changes into the plan which had been adopted, of which he 

 published an account before his return to Palermo. M. Cac- 

 ciatore, his own assistant and pupil, was, upon his recom- 

 mendation, appointed director of the new observatory. 



Piazzi took an active part in the labours of the commission 

 charged with the public instruction of Sicily. To this country 

 he had formed the deepest attachment, and though Napoleon 



