What Makes Up a Dippy?

This famous early Canadian power boat is generally known as the “Dippy “ or “Dispro” and was the brainchild of the late William J ‘Billy’ Johnston of Port Carling, Ontario, Canada. Mr. Johnston started working for his pioneer Muskoka boatbuilding uncle, William Johnston Sr. around 1900 and together they built many fine boats in the Muskoka area.

The Device

1914
W.J. Johnston Jr. (Young Billy), while working as manager of his Uncle’s Port Sandfield Rowboat Livery, was introduced to the concept of the disappearing propeller by a local engineer. Young Billy saw how the idea could be used in a rowboat with a newly available, light weight, gasoline engine. The critical “Device” allowed the propeller to be cranked up into a housing in the bottom of the boat out of danger from rocks or deadheads.

The Dippy

1915
The first Disappearing Propeller Boat was constructed in Uncle Billy’s boat shop in Port Carling. The boat was promoted as “The greatest little motor boat afloat”. The little boat commonly known as Dispro or Dippy attracted investors in a new corporation and by 1920 they were selling quickly from Sales Offices in Toronto and Buffalo for $325.00 f.o.b. Port Carling. Dippys were shipped to England, Ireland, France and Brazil.

What’s the Device?

The ‘device’ consisted of a cast iron housing (later aluminum) mounted in the hull to accommodate a universal joint, propeller shaft, combination strut-skeg and the propeller. The motor was mounted forward and was coupled to a flexible propeller shaft which entered the housing through a stuffing box. In the largely uncharted and unexplored waterways of that day, this device was truly a safe way to get there with little or no damage if the propeller shaft skeg struck bottom or logs, etc.