APPLICATIONS OF THE ELECTRIC LIGHT. 265 



850 revolutions per minute under always the same conditions as 

 regards the external circuit. According to Pouzolz's calcula- 

 tions, the best relation between the eclipses and appearances of 

 the light would be a light of 20 seconds and an eclipse of 100 

 seconds. 



"The height of the luminous focus is 10 metres above the 

 water, and the possible range of the light, in consequence of the 

 depression of the horizon, is 10 marine miles (18,520 metres) for 

 an observer with his eye at 6 metres above the water. 



" In order to light up the topsails and the gallant-sails while the 

 low sails are left in obscurity, Pouzolz had made a frustum of a 

 cone in tin-plate, and placed it in the movable lamp, with the 

 large opening outwards. In this way the Ameriqut was visible at 

 a great distance from ships and signal-stations when the captain 

 allowed the electric light to continue in action during the whole 

 night." 



It will be seen by this description that all the objections 

 offered to the use of the electric light on ship-board have 

 been removed by this new arrangement, and Pouzolz answers 

 those which have been made to the use of an intermittent 

 light by stating that the light produced by short flashes has 

 never incommoded the sight of any officer of the watch or 

 look-out man at the cathead, and that the brilliancy of the 

 green and red side-lights is not at all diminished by the use 

 of the lighthouse in front. 



Since the dreadful collisions which have taken place within 

 the last four years, there is now more inclination to resort 

 to the electric light for ships ; and we see that, according to 

 Fontaine's book, in 1877, a certain number of Gramme 

 machines have been set up on board several French, Danish, 

 Russian, English, and Spanish ships of war, among which 

 we may mention the Livadia and the Peter the Great of the 

 Russian navy, the Richelieu and the Suffren of the French 

 navy, and the Rumancia and the Victoria of the Spanish 

 navy. It remains to describe the projecting apparatus, 

 which, on account of the small space over which the light is 

 to be thrown, is different from the lenticular apparatus of 



