In reading The Discoverers: A History of Man's Search to Know His World and Himself, by Daniel J. Boorstin, I came across a reference to a fascinating historical character.
Giambattista della Porta was a true Renaissance man of Italy; he was a polymath and wrote intelligently on dozens of subjects. Most noteworthy is his Magica Naturalis, or Natural Magic, which appears to have been banned, then unbanned, by the Inquisition. The book was as much about what was understood in that time as "science," but also bristles with pseudo-occult matters.
I've not read it, just an abstract of its contents. One thing that I found fascinating was the so-called "sympathetic telegraph." I'll let Wikipedia explain it:
"In the book, Porta also mentioned an imaginary device known as a sympathetic telegraph.
The device consisted of two circular boxes, similar to compasses, each
with a magnetic needle, supposed to be magnetized by the same lodestone.
Each box was to be labeled with the 26 letters, instead of the usual
directions. Porta assumed that this would coordinate the needles such
that when a letter was dialed in one box, the needle in the other box
would swing to point to the same letter, thereby helping in
No information on whether he ever actually built this, and, surprise, later researchers confirmed this does not work. But it's a great idea for some form of long-range communication device in a fantastic fictional setting.
Another interesting bit about Porta was his genius in cryptography. He invented a method of writing secret messages on the insides of eggs. Again, from Wikipedia:
Cool! I am glad I discovered this interesting fellow, and I am sure both the sympathetic telegraph and crypto-eggs will make its way into my Swords Against Satan game setting (weird fantasy in Elizabethan England).
Boorstin's book The Discoverers, by the way, is an incredible adventure. It tells of man's struggles and triumphs in discovering (and making) the world around him, ranging from astronomy, time, geography, nature, biology, printing and other things. If you enjoy the historical segments of, say, Cosmos, you'd enjoy Boorstin.