A mention in a ’50s era issue of Computers and Automation led to this mystery. The best account is in McClure’s Magazine in 1914.
John Hammond was a visionary AND the heir to a huge fortune. The money and connections enabled him to turn his visions into large-scale reality. His first invention was a mechanical dog, using selenium cells.
Transcribed from the article:
Among other things that puzzled the visitors was a half toy (embodying the same scientific principle) that Hammond called his electric dog. The eyes of this melancholy creature are of bulging glass as large as saucers. His nose is a long thin strip of brownish reddish board. His body is an oblong mahogany box, and contains an electric motor, storage battery, two selenium disks, two relays, and two solenoid magnets. This dog has no tail except an electric switch, and he runs on three brass wheels, two in front and one behind.
When the motor inside of the dog is started he will do some extraordinary things. If you walk before him carrying a lantern, he will follow you, turning to the right or left as you turn, although you neither touch him nor control him in any way that you can understand. Briskly he steers himself after you with a fidelity that is positively uncanny until you learn that what guides him is the lantern, through the sensitiveness to light of that strange element, selenium. If you move your lantern to the left, the left selenium cell receives more light and more stimulation than the right cell, and so allows more current from the storage battery to flow into the left-hand magnet, which then deflects the hind wheel to the left and the dog turns in that direction.
Selenium-based cybernetics was remarkably well developed at that time. The Optophone, enabling blind people to read books, was an even more astonishing use of light-sensors. Selenium tech then faded for unknown reasons, finally re-emerging in the ’50s after other semiconductors were practical and profitable.
Hammond’s main goal was a remote-control ship. At first he tried using the same light technology, but quickly found that light was useless at the necessary distances. Radio was needed. So he built the most powerful wireless station in the world at the time, solely devoted to his experiments.
When the station, and the 40-foot remote controlled yacht, were ready to show, he invited the military to see it and try it.
The General came, bringing with him Colonel R. P. Davis of the Coast Artillery Corps, an expert in these matters. Together they witnessed the demonstration. They saw a boat swifter than the swiftest cruiser dart about the harbor under perfect control . They saw her instantly circle at the touch of a key. They saw her headed for a definite mark a mile away, two miles, three miles away, and strike it with precision every time — a mark that must have been blown into eternity had it been an enemy’s battleship.
Why didn’t this line of research continue? Mismatched goals. The military wanted to use radio for torpedos, not ships. Unlike modern autonomous car dreamers, they recognized that a ship needs full human control with advice by radio. Radio doesn’t work well underwater, so the radio controlled torpedo wasn’t practical with 1914 technology. Hammond continued to advance remote control tech, and his inventions played a major part in guided missiles. EETimes has a more complete biography.