Bache.l "" [April 17, 



necessary, even in laboratory experiments, to avoid action where 

 the phenomena appear in an exaggerated adverse form. I there- 

 fore next proceeded to deal with small but unconfined volumes 

 of liquid. 



"With the Wheatstone Bridge, with an electro-motive force of 

 one hundred and ten volts, and one ampere of current, I found 

 the resistance at two inches between the poles, placed vertically 

 in a hay-infusion, in a round glass dish about five inches in dia- 

 meter, to be 1560 ohms. Making the liquid a little shallower, 

 the other conditions remaining the same, the resistance rose to 

 2120 ohms. In a very narrow, rectangular receptacle, the other 

 conditions remaining virtually the same, the resistance rose to 

 8000 ohms. The poles being then placed in water, not in the in- 

 fusion, in the round glass dish, the other conditions being the 

 same as those in the first experiment, the resistance became 

 18,400. Slightly increasing the depth of water in the dish, the 

 resistance sank to 13,000 ohms. These rude experiments were 

 followed by a series conducted with two beautifully finished 

 wooden, shellaced boxes, of exactly the same length and depth in 

 the clear, but one of them of only half the width in the clear of 

 the other. Thus was obtained with precision in the larger of 

 the-two (but, of course, the same consequence would have ensued 

 with the smaller), by alternately making it exactly one-half full, 

 and then full to the brim, the result that the volume thereby ver- 

 tically obtained reduces by one-half the resistance of the lesser 

 volume. Thus, also, by filling both boxes to the brim was ob- 

 tained with precision the result that double the volume of liquid 

 horizontally obtained reduces by one-half the resistance of the 

 lesser volume. Therefore it was demonstrated that resistance in 

 water, as well as in metal, is inversely proportional to volume as 

 determining cross-sectional area, whether increased by vertical 

 or horizontal extension ; that is, is inversely proportional to 

 cross-section, as dependent upon volume ; and that in whichever 

 of these two directions volume is gained, it introduces, propor- 

 tionally, freedom of propagation of the electric force in and about 

 the imaginary right-line joining the poles. 



The result of a series of experiments, with the poles placed 

 apart at 2, 4, 6, 8, up to 12 inches, showed that the resistance, 

 whatever it may be, varies directly as the distance between the 

 poles, a result identical with that in electrically charged wire, 



