REASON OF MOVING FORCES. 375 



Now one day, according to tradition, the lid of the 

 saucepan, in which his dinner was being cooked, suddenly 

 rose. Worcester then considered the strangeness of the 

 phenomenon that he had just witnessed. The thought 

 now occurred to him that the same power which had 

 raised the lid might become, under certain circumstances, 

 a useful and convenient motive power. After recovering 

 his liberty, he described, in 1663, in a book entitled Cen- 

 tury of Inventions* the means by which he intended to 

 realize his idea. The essential part of these means, as 

 far at least as they can be understood, is the bomb half 

 filled with a fluid, and the vertically ascending tube, as 

 we just now described. 



This bomb, this same tube, are drawn in the Reason 

 of Moving Forces, a work by Solomon de Caus. There, 

 the idea is presented clearly, simply, and without any 

 pretension. Its origin has nothing romantic in it ; it is 

 not connected with the events of civil war, nor with a 

 celebrated state prison, nor even with the rising of the 

 lid of a prisoner's saucepan ; but, what is of infinitely 

 more importance in a question of priority, it is, by its 

 publication, forty-eight years older than the Century of 

 Inventions, and forty-one years anterior to Worcester's 

 imprisonment. 



Thus reduced to a comparison of dates, the debate 

 seemed to be brought to a close. Indeed, how maintain 

 that 1615 had not preceded 1663 ? But those persons 

 whose principal aim was to expel any French name from 

 this important chapter of the history of the sciences, im- 

 mediately changed their ground, as soon as they had 



* It is expressly stated on the title-page of this pamphlet, that it 

 was written in the year 1655, though not published till 1663. Trans- 

 lator. 



