382 THE INTELLECTUAL RISE IN ELECTRICITY. 



investigation ought only be undertaken among the con- 

 tents of museums. 



Browne, however, made one experiment which is of 

 especial interest, and which requires from us a glance back- 

 wards, and hence a brief digression. 



It has already been noted that John Baptista Porta refers 

 to possible communication "to a friend that is at a far dis- 

 tance from us and fast shut up in prison" by means of 

 "two Mariner's Compasses having the Alphabet writ 

 about them." 1 This is the first known suggestion of a 

 possibility which fretted men's minds for many years; 

 namely, that by reason of a supposed sympathy between 

 magnets, the movements of one would be copied by those 

 of another, no matter how great the distance between 

 them; and that, hence, it was necessary only to dispose 

 alphabets around two widely-separated pivoted needles, 

 which had both been magnetized by the same lodestone, 

 to cause the letter to which the needle at one station is 

 moved to be indicated simultaneously by the needle at the 

 other and distant station. Of course, this would now be 

 termed u telegraphy ;" and it would not be difficult to find 

 modern dial telegraph instruments operating in accord- 

 ance with a very similar process. 



Porta's idea appears to have been improved upon by 

 Daniel Schwenter, who, in 1600, devised an apparatus of 

 some complexity. He divided the compass card, in each 

 of the widely-separated compasses, into compartments each 

 containing four letters of the alphabet. The needle in 

 signalling was intended to move first to the compartment 

 containing the letter, and then to indicate the especial 

 character desired by one, two, three or four vibrations. 

 Just how the needles were to be worked by the bar mag- 

 nets or "chadids" which were employed is not clear; but 



1 Porta: Magia Nat., 1589, Book vii. Natural Magic (Eng. Tran.). 

 1658, Book vii, p. 190. 



