[ 3^2 ] 



LXVlll. Neio Outlims of Chemical Philosophij. By Ezekiel 

 Walker, Esq. of Lynn, Norfolk. 



[Continued from p. 24-5.] 



JL HE electrical apparatus, mentioned in my last paper, consists 

 of about 3,300 groups of zinc, copper, and paper discs, inclosed 

 in six glass tubes. These are placed in an horizontal position, 

 each resting- upon two insulating rods, which stand seven inches 

 high above the common base into which thev are fixed. In the 

 manner of connecting the ends of the tubes there is nothing 

 new, but in the application of the silver leaf electrometer, there 

 is a mode which may afford some amusement to those who are 

 not much acquainted with physical experiments. 



The wire on the top of the electrometer may be placed either 

 in contact with one extremity of the arrangement of columns, 

 as represented in the figure*, or at any more convenient di- 

 stance. The electrometer being placed upon a table in the 

 middle of a room, and the electrical apparatus in some remote 

 place, out of sight, it only requires a thin music wire to connect 

 the apparatus with the electrometer, to cause the pendulums to 

 vibrate as freely as if the electrometer and colunms were in ac- 

 tual contact. 



It has been supposed by M. De Luc and some other writers 

 on this subject, that the variable action of two electric columns 

 upon a pendulum suspended between them, is owing to the 

 moisture contained in the atmospliere; but others are of opinion 

 that the temperature of the air, and not moisture, is the cause of 

 this variation. 



To determine the cause of irregularity in the vibrations of my 

 pendulums, I made observatioris several times a-day, for more 

 than a month, and I find that their vibrations are governed by 

 the temperature of the air of the place in which the apparatus 

 stands. The moisture of the atmosphere, I apprehend, could 

 produce no effect, as the ends of the glass tubes were carefully 

 closed with sealing-wax. 



The following observations show the effect of temperature 

 upon electric columns : 



* PaM 213 of this volume. 



In 



