24 PHILOSOPHICAL TRANSACTIONS. [aNNO 1776. 



different circuits are made between its positive and negative side, some electricity 

 will necessarily pass along each ; but a greater quantity will pass through those in 

 which it meets with less resistance, than those in which it meets with 

 more. For instance, let a person take some yards of very fine wire, 

 holding one end in each hand, and let him discharge the jar by touching 

 the outside with one end of the wire, and the inside with the other ; he will 

 feel a shock, provided the jar is charged high enough ; but less than if 

 he had discharged it without holding the wire, in his hands ; which shows, that 

 part of the electricity passes through his body, and part through the wire. 

 Some electricians indeed seem to have supposed that the electric fluid passes 

 only along the shortest and readiest circuit ; but besides that such a supposition 

 would be quite contrary to what is observed in all other fluids, it does not agree 

 with experience. What seems to have led to this mistake is, that in discharging 

 ajar by a wire held in both hands, as in the above-mentioned experiment, the 

 person will feel no shock, unless either the wire is very long and slender, or the 

 jar is very large and highly charged. The reason of which is, that metals 

 conduct surprisingly better than the human body, or any other substance I am 

 acquainted with ; and consequently, unless the wire is very long and slender, 

 the quantity of electricity which will pass through the person's bodv, will bear 

 so small a proportion to the whole, as not to give any sensible shock, unless the 

 jar is very large and highly charged. 



It appear") from some experiments, of which I propose shortly to lay an 

 account before this society, that iron wire conducts about 400 million times 

 better than rain or distilled water ; that is, the electricity meets with no more 

 resistance in passing through a piece of iron wire 400,000,000 inches long, than 

 through a column of water of the same diameter only one inch long. Sea 

 water, or a solution of one ])art of salt in 30 of water, conducts 100 times, and 

 a saturated solution of sea salt about 720 times better than rain water. 



To apply what has been here said to the torpedo ; suppose the fish by any 

 means to convey in an instant a quantity of electricity through its electric organs, 

 from the lower surface to the upper, so as to make the upper surface contain 

 more than its natural quantity, and the lower less ; this fluid will immediately 

 flow back in all directions, part over the moist surface, and part through the 

 substance of its body, supposing it to conduct electricity, as in all probability it 

 does, till tiie equilibrium is restored : and if any person has at the time one 

 hand on the lower surface of the electric organs, and the other on the upper, 

 part of the fluid will pass through his body. And, if he has one hand on one 

 surface of an electric organ, and another on any other part of its body, for in- 

 stance the tail, still some part of the fluid will pass through him, though much 

 less than in the former case ; for as pnrt of the fluid, in its way from the upper 

 surface of the organ to the lower, will go through the tail, some of that ])art 



