164? Application of Electro-magnetism to Navigation, 



inches by 8 inches) and is about 9 inches in height. Behold 

 certainly a beautiful application of the voltaic battery. 



In the application of electro-magnetism to the movement 

 of machines, the most important obstacle always has been the 

 embarrassment and difficult manipulation of the battery. This 

 obstacle exists no longer. During the past autumn and at a 

 season already too advanced, I made, as you may perhaps 

 have learned by the gazettes, the first experiments in naviga- 

 tion on the Neva, with a ten-oared shallop furnished with 

 paddle-wheels, which were put into motion by an electro- 

 magnetic machine. Although we journeyed during entire 

 days, and usually with 10 or 12 persons on board, I was not 

 well satisfied with this first trial, for there were so many faults 

 of construction and want of insulation in the machines and 

 battery which could not be repaired on the spot, that I was 

 terribly annoyed. All these repairs and important changes 

 being accomplished the experiments will shortly be recom- 

 menced. The experience of the past year combined with the 

 recent improvements of the battery give as the result, that to 

 produce the force of one horse (steam-engine estimation) it 

 ■will require a battery of 20 square feet of platina distributed 

 in a convenient manner, but lliope that from 8 to 10 square 

 feet will produce the effect. If heaven preserves my health, 

 which is a little affected by continual labours, I hope that 

 within a year of this time, 1 shall have equipped an electro- 

 magnetic vessel of from 40 to 50 horse power. 



In my paper, " On the application, &c.*" I have spoken 

 of the influence v^hich those magneto-electric currents which 

 you had discovered a short time before, would exert on the 

 progress of electro-magnetic machines. They are properly 

 the cause that the expectations which have been entertained 

 regarding these machines have not as yet been fulfilled. But 

 if one examines them more nearly these currents are not so 

 disadvantageous as have been supposed. Experiments which 

 I have made by interposing a galvanometer or a voltameter 

 liave taught me that during the action of the machine the 

 electrolytic action of the battery is much less, and sometimes 

 not more than half that which takes place when the machine 

 is stopped, the current still passing by the helices which sur- 

 round the bars of iron. Thus if on the one part the magneto- 

 electric currents diminish the force of the machine, on the 

 other the electrolytic dissolution of the zinc, which makes the 

 greatest part of the current expense, is at the same time con- 

 siderably diminished. I have not as yet succeeded in com- 



* See Taylor's SciENTiric Memoirs, vol. i. p. 503, and vol. ii. (Part V.) 

 p. 1. — Edit, 



