ANALYSIS OF THE GALVANIC PILE. £.. 



to the condenser, which it made negative. I repeated the 

 experiment without tour/ling the copper di^k lying on the 

 zinc disk, and the negative effect was of the s;:me quantify. 

 In general, a greater number of alternate contacts is re- 

 quired to produce the same quantity oi" negative effect with 

 topper ', than of positive with zinc. 



We see however in this experiment the same phenomenon 

 as in the preceding, in this respect, that when zinc and 

 copper are in mutual contact, the former takes some electric 

 fluid from the latter, which, on its opposite side, it shares 

 with other bodies; in the first experiment it shared this 

 fluid with the condenser, while the ground restored it to the 

 copper disk ; in the last, zinc, communicating that acquisi- 

 tion to the ground, took more fluid from the copper disk, 

 which made the condenser partake of its loss. This is the 

 leading thread with respect to the motion of the electric 

 fluid in the pile, and I shall follow it; but 1 must iirst speak 

 more particularly of the anomalies observed in these expe- 

 riments, which are important. 



These differences, sometimes very great, in the quantity Anomalies in 



of effect of the same operations, surprised me at first; and these ex P en * 



, . ... ' ; ... meats, 



suspecting something amiss in the condenser, 1 examined it 



closely, without tinning any defect: then at other times, 

 without any change, 1 found the same effects. At last I 

 remarked that, commonly, the greatest effect? in the same 

 day were in a part of the morning, and the smallest towards 

 the evening; and thnt these effects differed also, in intensity 

 on different days. Now this is what I have said above of 

 the spontaneous effects of the pile, which is composed of a 

 succession of the same binary groups of metals ; and thus 

 the condenser, when applied to these experiments, is also a 

 meteorological instrument. And there is a remarkable cir- 

 cumstance in this respect; that often at the same moment 

 there is a great difference between the effects on the con- 

 denser of the opposite extremities of a small pile; but 

 sometimes it is the negative side which prevails, and at other 

 time s it is the positive. This manifests, that the ground, 

 with which the opposite side of the small pile communi- 

 cates, in the f rmer case possesses less, and in the latter 

 more of the electric fluid than the ambient air. But thi.s will 

 fce one of the subjects of the following paper. 



After 



