The following info was compiled from 19th century documents and written by E. Craib, not Jack. :-)
I am fond of electric rowboat motors, as I enjoy hearing the birds and frogs and insects when I am on the water. That's not to say I don't really appreciate internal combustion rowboat motors - I do very much; I'm just not fond of them. Their great noise and drama is just what makes a small boy's eyes go round with excitement and wonder! Big boys, too.
Gustave Trouvé seems to have been the first man to design an electric motor planned to be easily detachable from the stern. Reporters commented that the ability to remove the rudder and the propulsive power and carry it away under your arm would be "a useful quality in the explorations of new countries". (What can I say?)
Previously, a half century earlier in Russia, Jacobi had batteries powering motors that turned paddlewheels. Reportedly the batteries gave off such noxious fumes they sickened and drove away the onlookers. It didn't catch on. That was in 1839, the year of Trouvé's birth.
Trouvé benefited from the intervening years of battery development plus his own experimentation. He was a practical man fascinated by electricity, working to develop ways to use it, with batteries as the source, and his rowboat motor may have been more of a proof of practicality than a passion to putt. Nonetheless, after the Universal Electrical Exposition of 1881 at which his Eureka rowboat motor was officially debuted, witnessed by the commisioner of the exposition, by a representative of the Revue Scientifique and by a representative of the Russian navy, 300 of his motors were reported to have been built and used on the Seine for the enjoyment of holiday makers. I have no idea at this time who actually produced the 300 motors.
Trouvé's background makes his development of the Eureka even more understandable, given that his more mature interests lay in the new field of electricity. His first job after leaving a College of Arts and Trades had been as an apprentice to a clockmaker! Then it seems he went on to do mechanical work for others, gaining a wide range of experience and gaining enough confidence to design his own devices. This rudder motor was a piece of cake to design. His motor was described as a modification of the Siemens coil placed on the rudder head with a chain drive to the propeller.
Confidently, Trouvé said, “I had the honour to submit to this (French) Academy (of Science), in the session of 7th July 1880, a new electric motor based on the eccentricity of the Siemens coil flange. By suggestive studies, which have allowed me to reduce the weight of all the components of the motor, I have succeeded in obtaining an output which to me appears quite remarkable."
His actual first invention has had greater impact on the world - the first practical electrically lit endoscope. It was used when probing for a bullet in Garibaldi's foot in 1862!
The second engraving of his motor on the right is from "Electricity in the Service of Man: a popular and practical treatise on the applications of electricity in modern life"
Alfred Urbanitzky (Ritter von)
Cassell & Company, Ltd., 1886
And, while it has nothing to do with rowboat motors, at the bottom of this page you have to check out his Electric Jewels, worn at the Folies Bergere by the dancers to the amazement of the crowds.