TRANSACTIONS OP TUB SECTIONS. 
27 
I tire merely observations of declinatioD, because these are independent of cor- 
iKOtms for temperaturp, changes of magnetism, &c., which render it a very difficult 
aittfrtoinake the indications of the other instruments agree exactly. I must add, 
tk 4e diferences are not owing to an error or uncertainty in marking : the mag- 
mpajiiuc bars are furnished with tnirrors and can be observed in the usual way. 
Ik dsffTitioiis made in this way.whUe the instrumcuU were marking, have m 
flKj CISC shown that the marks are perfectly correct. . j 
UrmsUameatB, as I have mentioned before, mark forty-eight hours ; the cylinders 
Bciimit one inch in diameter. There would be no difficulty in making the instru- 
w!! go for several days, or mark every quarter of ou hour. I think observations 
nit (wry quarter of on hour would bo extremely valuable. 
1 remain, dear Sii', yours most truly, 
Lamont. 
On Galvanic Co»w-wio«. jBy jMr* Mahper. 
All vliD are familiar with voltaic batteries have experienced the inconvenience of 
®t»cting the positive and negative poles with other inatrumeuts, and when sacral 
Cnksare employed, of connecting one to ruiothpr, in consequence of the stubborn- 
' ’'ufthemres commonly used, and the time taken np in mnnging the bmdiiig- 
*awaiid wires. In order to obviate much of this inconvenience, I beg to lay be- 
^tk* members a method which I have successfully audopted, which only suggested 
'klftoiiie last week {it is by using a tliin wire spirally fomied, at each end of which 
“'hefeof three or four turns, which helices lieing slipped on a of brass, 
—tii or fixed by a screw to the battery nr other instrument.—this I have found ^ 
k»«ifficient contact in cverv case in which it has Iwen tried. By this method 
wnfwooa have been covered with copper in the electrotype process for knobs ot 
^’kajws, &c'. 
fif the Antagmiism of Uml and l£lectrimh/ ; and also oj the Singleness 
'll fhe. Electric Fluid; with some liemarhs on the NaUitcoj Conduction Mid 
By Sir Gbaves C. IIaucuiton, A’.i/., M-A,, F.R.S., For, 
of the Instilatc of France, 
Alllhin, porous bodies, derived from the vegetable and animal kingdoms, if uot 
‘^“'Sifnlhofan inch in thickness, may ho tutnlig dcpriveii of their electricity by 
2; holding them before a giKid fire for four or live .seconds ; and, what is very 
••“hie, though they will in a few seconds reacquire their former humidity, tney 
• M regain dwir coaling of normal electricity before six or seven days nave 
M, even in damp vrealhcr. Wbeu the same substances were pasted upon 
JJw wotHi. they could not be lUprWt^ of their electricity by the greatest degree 
^.diat could be applied without horning. -The author wos 
2^0 paper nf its dectricitv bv the preceding proers*, to connect aOO slip^ge- 
”7ttcrdy smanlv rubbing the niipermost six or seven times m one d^tion 
? rubber. When the slip* were tested, it was found hl‘»t th® greorest 
were in a we^aliet, and tlio rest a ywUU'e .state, though Indi 
only positive eWiritity to paper. On the use of a J 
nr^lWc electricitv to the slip of paper which 19 without 
found to be either in a positive or negative state, but without 
of succession. On holding the same papers, tuUlly depri 
ki ftv prime conductor of a plate machine, the positive electncity, . , 
throughout them,rDn*ml some k-avxs p/w. which 
.^ result took place when the Blips were held close to the ^^^‘".“^cories. 
5J[5i*’'!]'®«’»n'onicated only negative electricity, [.-.-h becomes 
tlu.«. facta the author infem that there is but one lluitl, which becomes 
Tbp ’“‘d negative bv diatributioo. that it 
i invertipitet the nature of conduction, ^ 
^ Ihs attraction beUveS the fluid, and the nK’tallic T other w^en 
i<n^ J **11 therefore conductibility and affinity are the soni^- P ' 
^ opinion thaJaa'midlicS'ariBes from on attraction between the metal and 
