marine propulsion; to make it easy to carry his marine conversion to and from his workshop to the nearby River Seine, Trouvé made it portable and removable from the boat, thus inventing the outboard engine. On 26 May 1881 the 5m Trouvé prototype, called Le Téléphone reached a speed of 1 m/s (3.6 km/h) going upstream at 2.5 m/s (9 km/h) downstream. Trouvé exhibited his boat (but not his tricycle) and his electro-medical instruments at the International Electrical Exhibition in Paris and soon after was awarded the Légion d'Honneur. He also miniaturized his electric motor to power a model airship, a dental drill, a sewing machine and a razor. Gustave Trouvé next invented his "Photophore", or battery-powered frontal headlamp, which he developed for a client, Dr Paul Hélot, an ear-nose-and throat specialist of Rouen. This wearable, direct shaft, lighting system could be oriented by head movements, so freeing the hands of its wearer. A file of correspondence between these two men enables one to place this invention during 1883. Trouvé soon modified their frontal headlamp both for use by miners, rescue workers, and later by speleologists, in dark surroundings, but also by tinting the light with various colors as theater jewelry for artiste troupes in Paris and Europe. The latter became known as "luminous electric jewels" and was the forerunner of today's wearable technology. In 1884, Trouvé fitted an electric boat with both electric horn and a bow-mounted frontal headlamp, the first time such electrical accessories had ever been fitted on any mode of transport. He developed a portable electric safety lamp. In 1887, Trouvé, whose brand name was Eureka (Greek: εὕρηκα =“I have found”, translated into French “J’ai trouvé), developed his auxanoscope, an electric slide projector for itinerant teachers (1887). Around the same period, Trouvé, a confirmed bachelor uninterested in commercialization, turned his fertile mind skywards. Convinced that the future lay with heavier-the-air machines, he flew a tethered model electric helicopter, the ancestor of the Sikorsky Firefly. He next built an ornithopter, the wings of which flapped using a rapid succession gun cartridges, enabling it to make a noisy but at the time unheard-of flight of 80 meters. In 1889, he also fitted the battery-electric rifle he had developed in 1866, with a frontal light enabling nocturnal hunting. He also developed a battery-electric alarm system for nocturnal fishing. The 1890s In 1891 Trouvé developed electric multi-colored fountains for domestic