The Vail Lever Correspondent Key.

Below can be seen the first ever "lever arm" Telegraph Key that Alfred Vail (Samuel Morse's assistant) both designed and built. He called this the "Vail Lever Correspondent" Two were made for use in the experimental Washington - Baltimore telegraph line (May 24 1844) that was a huge success.

A very rare and beautiful key. The wooden base measures about 7 1/8" Long, by 1 7/8" Wide, by 7/8" High. (180 x 47 x 21mm).

Smithsonian Institute

"BK"