Viking Motor Company
Grinnell, Iowa

Never saw one of these.

below - 1919

ANY small boat can be made a practical, useful power boat in a few moments with the Viking Detachable Watercraft Motor.
It is not merely a convenience—it isn't a makeshift. It is a scientifically designed, strongly built piece of machinery.
Throw away the oars and paddles—attach the Viking—skim away under your own dependable power.
The Viking has speed— twenty-five per cent more than other detachable motors.
It starts with a mere turn of the fly wheel. No exhausting, temper destroying labor turning it over. The high tension magneto and scientific float feed carburetor mean a speedy get-away.
And you can go under power anywhere you can float the boat. In a jiffy you can raise the propeller so it won't tangle in weeds or drag in shallow water. No special tools—no attachments of any sort are required.
The Viking weighs but 55 pounds complete and occupies no more space than a suit case. You can carry it easily or dump it in the back of the car.
It's the most practical detachable motor for any small boat.

This is the text of an ad for this antique outboard motor.