120 ARTHUR E. SHIPLEY 



graving of a portrait of Lorenzo (d. 1648), 

 the brother of Cosimo II, which shows an as- 

 tonishing resemblance to Charles II ; and it is 

 interesting to remember that Cosimo II earned 

 his chief claim to the gratitude of posterity 

 by his courageous encouragement, protection 

 and support of Galileo, who owed to him the 

 opportunity and means of making his famous 

 astronomical discoveries. 



Another royal personage, Prince Rupert, 

 "full of spirit and action, full of observation 

 and judgment," about this time invented his 

 "chemical glasses which break all to dust by 

 breaking off a little small end: which is a 

 great mystery to me."^' He had, says Gra- 

 mont, quelques talens for chemistry and in- 

 vented a new method for making gunpowder, 

 for making "hails hot" and for boring cannon. 

 His traditional invention of the almost lost 

 art of mezzotint is probably due to the fact 

 that, at an early date, the real inventor, Lud- 

 wig von Siegen, explained to him his process 

 and that Prince Rupert demonstrated with 

 his own hands this new method of engraving 

 to Evelyn. 



•Pepys, 13 Jan. 1662. 



