I am writing to protest Peter Baida’s slur against Thomas Edison (June/July), namely, that Edison himself thought his phonograph “not of any commercial value.”

Once when I was at the Edison National Historic Site in West Orange, New Jersey, the tour guide showed us the first phonograph and described what happened when Edison’s “Mary Had a Little Lamb” squeaked back from the rolled band of tinfoil. Not one but several of Edison’s employees fell to their knees and wept openly at this miracle.

Further, Edison vowed early in his career never to invent anything that was not marketable. He decided this after his first patented invention, an automated vote-tallying machine, was rejected by politicians who preferred the manual tallying method as politically advantageous. Edison, in fact, originally envisioned the phonograph as primarily a business machine for recording correspondence.

Much of Edison’s Menlo Park equipment and material from his Florida workshop has been moved to Dearborn by Henry Ford. Tour guides there confirmed that Edison invented solely where there was a market for the product. Witness his electronic pen (the first office copier), as well as his struggle to extract rubber from goldenrod, an attempt he abandoned when synthetic rubber developments rendered goldenrod rubber unprofitable. Edison, in fact, viewed the phonograph as the means to provide for his old age.