THE FLORENTINE ACADEMY. 433 



solid or fluid, except a plate of iron and steel. Of the 

 electrical experiments one is of great importance, for it is 

 the same which so much puzzled Robert Boyle. The 

 Academy, however, was by no means mystified, nor need 

 Boyle have been so had he read the clear description of it 

 which was already in the archives of the Royal Society, 

 to which the transactions of the Florentine Academy had 

 been solemnly presented by emissaries from Leopold in 

 1667. How important this experiment was, will now soon 

 appear; meanwhile, note how clear the Florentine philoso- 

 phers' perception of it, in contrast to Boyle's obscurity. 



"It is commonly believed," they say, 1 "that amber at- 

 tracts the little bodies to itself; but the action is indeed . 

 mutual, not more properly belonging to the amber than 

 to the bodies moved, by which also itself is attracted; or 

 rather it applies itself to them. Of this we made the exper- 

 iment, and found that the amber being hung at liberty by 

 a thread in the air, or counterpoised upon a point like a 

 magnetical needle, when it was rubbed and heated, made 

 a stoop to those little bodies which likewise proportionally 

 presented themselves thereto and readily obeyed its call.'*' 

 Such was the first announcement of the mutual attraction 

 of electrified bodies corresponding to the mutual attrac- 

 tion of magnet and iron which Gilbert had recognized. 



Let us now recall some facts which, to the intelligent 

 student of physics attending the meetings of the Royal So- 

 ciety toward the end of the iyth century, might seem as 

 fairly well established. 



Standing apart by themselves, he perceives four things, 

 each able to control mechanically other things even at a 

 distance and without apparent means of communication. 

 These are first, the sun which controls the earth ; second, 



1 Saggi di Natural! Esperienze fatte nelPAccad. del Cimento. Flor- 

 ence, 2d ed., 1691. Waller: Essayes of Nat. Exp'ts made in the Acade- 

 mie del Cimento. London, 1684, 128. 

 28 



