Name that name

An eponym is a word derived from an individual's name. Here are thestories behind some well-known eponyms.

1. This code of 63 characters in a dot matrix was published in 1829 by a 15-year-old French boy. Following an experiment with a military system called night-writing, he created a raised alphabet for reading and writing by touch. The young inventor, himself sightless, had learned the alphabet by feeling twigs shaped into letters. His new system's name?

2. This large tuba that encircles a player was named after an American composer and bandmaster who suggested its form. The "March King" led the United States Marine Corps Band for 12 years starting in 1880 and wrote more than 100 marching tunes, including "The Stars and Stripes Forever." What's the instrument's name?

3. This dot-dash code was named after its inventor, an American portrait painter better known for his work with the telegraph than the paintbrush. The first telegraphic message, sent between Baltimore and Washington, was "What hath God wrought?" on May 24, 1844. The code's name?

4. He's the man behind the "W" on light bulbs, but his major contribution was a more efficient steam engine. Nonetheless, the unit of electric power was named after this Scottish engineer. Do you know his name?

ANSWERS:

(1) Braille, invented by Louis Braille (1809-52), a teacher and organist who composed music in Braille, too; (2) the sousaphone, after John Philip Sousa (1854-1932); (3) Morse code, after Samuel F.B. Morse (1791-1872); (4) the watt is named after James Watt (1736-1819).