Today, we take for granted the ability to use our cell phones to turn off the lights or monitor a security system. Industry has used similar technology for decades to monitor machinery at remote locations over land line phones.
By chance, I recently saw a reference to an old magazine article about the first device to allow remote monitoring and control by phone. It was invented at Westinghouse by R.J. Wensley, and it was called the Westinghouse Televocal Supervisory Control System.
Westinghouse had a remarkably accurate vision for where this technology could lead–everything from automated sentry tasks for the military to turning on an oven remotely.
What surprised me the most about the article was when it was published. You can find it in the November 12, 1927, edition of The Literary Digest.