According to the Greek historian Herodotus, around 500 BCE Histiaeus wanted to urge his ally to revolt without raising suspicion. He had a trusted slave's head shaved, tattooed the message on his scalp, and waited for the hair to grow back before sending him. On arrival, the recipient simply shaved it again. It's an early example of steganography, the art of hiding that a message even exists.
In 1843, inventor Alexander Bain patented a way to send images over telegraph wires using synchronized pendulums. By the 1860s, a commercial fax service was already linking cities. The telephone wasn't patented until 1876, more than three decades after that first fax patent. The fax is really a child of the telegraph age.
On 8 October 1958, in Stockholm, 43-year-old Arne Larsson received the very first implanted pacemaker. The device, designed by engineer Rune Elmqvist and implanted by surgeon Åke Senning, worked for only a few hours and had to be replaced. Larsson went on to receive more than twenty pacemakers in his lifetime. He died in 2001 aged 86, outliving both the engineer and the surgeon.