82 AERIAL COLUMN AXD AEKIAl KLECTROSCOPE.* 



experiments led me to the discovery of an electric apparatus, 



which, without any liquid, and' composed only of alternate 



zinc plates, and equal pieces of Duick gilt paper, produces 



strong electric, but i.o chemical effects. 



.'Spontaneous 2- ^'^J paper. Sir, in your Journal for October, 1810*, con- 



electijc raa- tains the description of a small apparatus of this kind, which, 



in order to distinguish it from the gri/i;a72fc/>i/e, I have named 



electric column. It is really a spontaneous electric machine, the 



ot unlimited power of which can be increased without limits, by increasing 

 power and ,, , ^ , .... ^ t , •,, i -• 



duration. ^"^ number ot the groups : at is lasting ; for I have still the first 



column, (that represented in the^^«re-j) which I constructed 



five years ago, preserving still its power : and indeed there is no 



reason why it should lose it, as there is no liquid to affect the 



' wze/a/5 5 for it requires only that the pa/;e/.s should possess the 



small degree of moisture of the surrounding air. 



(Joliunn of 3. As to the increase of power of this, natural electric ma^ 



SOOOf) pieces, chine by increasing the number of the groups, a very ingenious 



V. 1./ cu. ^^^ well-known experimental phiJosopher, Mr. W. Allen, 



has carried it to such a degree as to produce very remarkable 



effects. His apparatus con.si^tsof ten columns, each containing 



1000 groups cA zinc dudi Dutch-gilt paper, ^oxm'mg together a 



series of 10,000 groups : but they are of a small size, so as to 



be enclosed in glass tubes ; a circumstance, the effect of which 



shall be seen. The following are the phaenomena observed 



by Mr. AUen, which confirm • me points which I have stated. 



Jar ciiarged i. Havi ig tried to c/ia?o-e a coaled jar, the charge arrived 



by it. . J ' ^ 



sometimes to such a degree, as to give a shock up to the elbows j 



but at other times it could never arrive at that point. This cir- 



curo.;tance is owing to what I had observed of the influence of 



the electrical stale of the air. 



Did not de- 2. Notwithstanding such electric power, Mr. Allen did not 



coinpost: vva- perceive any production of gasses in glass lubes with water, 



made to connect the evlremities of these columns. 



Effect of size 3. That apparatus shows also what I had found with respect 



and number of to the size of the plates; that the size was indifferent to the ?w- 



^ ^ ^^' tensity of the ultimate effect ; but that the larger they were, 



the sooner that effect was produced. The plates of Mr. Allen 



being sjnall, many minutes were required to charge his jar. 



* Vol. xxvii, p. 81. t 11). p!. ili. 



4. I 



