. Method ofjiliing up Mr. De Luc*s Electric Columii, 209 



series (insulated,) in a box. and' brought wires from the 

 ends of this combined apparatus, which I made communi- 

 cate with two bells. I placed, on Tuesday 27th Febi'uary 

 1810, this apparatus in a closet, where I left it until Sun- 

 day 1 1th March, the bells continuing to ring (as far as my 

 observations went) from the time they were put \i\Xo the 

 closet until ^hat day; when they ceased. What was the cause 

 of their stopping 1 do not knovyi, but imagine it was owing' 

 to dampness. I cannot ascertain that they ransj'the whol'e^ 

 timewithoutstopping, but have no reason to believe (Other- 

 wise. I intended some months agii to have sent you the 

 description of the abov^-mentioned apparatus with cxperi- 

 nieiUfiy 'but deferretl sending it on account of Mr. De Luc's^ 

 paper not being published, which he sent to the Royal So- 

 ciely in Marchj last year, and which contains a description 

 of the electric column and its properties. He hopes 

 soon to publish^it himself. In the meantime he has per- 

 Tnitted me to communicate my account to you. I consider 

 the in\;ention of this column as the most important dis- 

 covery in the science of electricity since that of th6 7^/- 

 iaic pile, and do not doubt but that when Mr. De Luc 

 gives his paper to the public, it will prove extremely inte?-' 

 resting, and J have reason to believe it may lead to further 

 discoveries which will be considered as very important in 

 this branch of science. - ' 



Description of the Figures* 



Fig. 1. A column of 500 series of plates about l-ths of atij 



inch diameter, in a glass tube with" bras^c.^ps, Sec' 



AA Brass caps, the ends of which screw on and off. 



BB Screws which pass through the caps into the 



V tube, having a brass plate at the end for com- 



press'ng the electric colunm. 

 CC Balls at the outer ends of the screws. 

 Fig* 2. One of the screws with a ball at the outer end, and 

 a brass plate or circle at the other. A small hole 

 is pierced in this plate, through which the silken 

 string connecting the electric column may p?ss. 

 Fig. 3. A smaller column (the plates of which are about -|th 

 of an inch diameter^) fitted up with a cork head 

 and tail to represent an eel. 

 Fig. 4. Size of plates in larger column. 

 Fig. 5. Ditto of the smaller one. 



Fig. 6. A combined apparatus, consisting of three rodd 



resting on insulating stands, .and having a wire 



projecting from each of the outer rods ; these 



Vol. 3^. No. 143. March 1810. O wires 



