IGi ANNUAL OF SCIENTIFIC DISCOVERT. 



. ELECTRICAL FLYING FISH. 



The experiment of the "flying fish" has excited attention in 

 Paris. M. rAl)l)e L:il)onle and M. Sallei-on have both written to 

 •' Les Mondes " on the subji.'ct. Each suggests making use of the 

 conductor of an electrical machine in place of a charged Leyden 

 jar. M. TAblie Laborde says, in the following manner the exper- 

 iment can be easily made by any who possess an ordinary electri- 

 cal machine : A piece of gold leaf or silvered paper is cut into the 

 shape of a kite ; this is then i)laced on the conductor of a machine, 

 and a ball connected with tiie rubber slowly approached to the 

 blunt end of the leaf. Soon the leaf rises and springs from the 

 conductor, remaining iiovering in the air between it and the ball. 

 The finger can be substituted for the ball, and the leaf led even ver- 

 tically round the conductor with a considerable intervening space. 

 The tlistance of tlie leaf from the ruljlier almost entirely depends 

 upon the size of the blunt angle, — the more obtuse this angle, the 

 nearer the leaf approaches to the rubber. The explanation given 

 by M. TAbbe Laborde is, that the jioint presented to the electrified 

 body, receiving electricity of the same name, is repelled, which 

 it would be altogether, were it not that it i)arts with its elec- 

 tricit}' by the other point, can be again attracted to the electrified 

 bo(h', and is again repelled. Thus repulsion takes place in ap- 

 proaching the conductor, because it receives more than it loses ; 

 but immediately attraction ensues, because now it loses more than 

 it receives. The equililjrium between these two opposing forces 

 enables the gold leaf to maintain itself in the air at a distance from 

 both solid bodies. 



ELECTRICITY IN DEEP-SEA SOUNDING. 



In deep-sea sounding, the greatest difficulty is felt, even by ex- 

 perienced persons, in ascertaining the precise moment at which 

 the lead of the sounding-line touches the bottom, — a matter on 

 ■which the whole value of the sounding dejiends. An apparatus 

 invented in France, at Lyons, removes, it is said, evei*y difliculty 

 on the point. The sounding-line contains within it, along its whole 

 length, two insulated conducting wii'es, the uiiper ends of which 

 ai'e connected i*espectively with the poles of a galvanic battery in 

 the ship. The lead is in two paits, the lower one of which is jjartly 

 inserted into the upper, and is capable of a limited vertical motion 

 within that of the other, so that, when left to hang freely, a small 

 empty space is left within the upper portion by the spontaneous 

 descent for a short distance of the lower portion. To the upj^er 

 end of the lower portion, and within the ujjper jjortion, is attached 

 a commutator, which is contained in an insulating and water-proof 

 sheath, and which, when the lower portion of the weight is raised 

 by contact with the ground, comes in contact with the ends of the 

 conducting wires, so as to complete the circuit. Instantly, by 

 means of the ordinarj- electro-magnetic apj^aratus, a bell is rung 

 on board the ship to attract the attention of the sounder, and a 

 ratchet is thrown into action, which "Urrests the unwinding of the 



