The Playfair cipher was invented in 1854 by an English scientist and inventor of many scientific breakthroughs of what era?
Playfair cipher: The Playfair cipher or Playfair square or Wheatstone-Playfair cipher or Wheatstone cipher is a manual symmetric encryption technique and was the first literal digram substitution cipher. Playfair cipher:  The scheme was invented in 1854 by Charles Wheatstone, but bears the name of Lord Playfair who promoted the use of the cipher. Charles Wheatstone: Sir Charles Wheatstone FRS (6 February 1802 – 19 October 1875), was an English scientist and inventor of many scientific breakthroughs of the Victorian era, including the English concertina, the stereoscope (a device for displaying three-dimensional images), and the Playfair cipher (an encryption technique).
Victorian era