'E.T. Holmes made the first one of these in 1877 to serve 6 telephone subscribers in Boston'
Telephone Switchboard (even though there were only 6 subscribers)
INVENTIONS: E.T. Holmes made the first one of these in 1877 to serve 6 telephone subscribers in Boston
E.T. Holmes made the first one of these in 1877 to serve 6 telephone subscribers in Boston
E.T. Holmes made the first one of these in 1877 to serve 6 telephone subscribers in Boston
INVENTIONS
Telephone Switchboard even though there were only 6 subscribers
INVENTIONS