84 
ELECTRIC COLUMN OF 20,000 PLATES. 
An electric 
column of 
discs of silver 
zinc and 
papers 
consisting of 
we thousand 
1 . When oil is poured or dropped on water, it spreads on all 
sides, with astonishing rapidity (I suppose 5 or 6 yards in a 
second) and smooths the surface by suspending the effect of the 
wind in forming the primary waves ; but it does not destroy the 
larger waves or the swell, nor prevent the undulations from 
being transmitted from the rougher parts into the smoother. 
2 . The smoothed surface is carried gradually to leeward, and 
after a short time, perhaps two or three minutes, a large pond, 
upon which oil has been poured, will become as rough as at 
first. 
3 . The man was drowned about a fortnight before the frost 
came on 3 which seems a long time for the oil to have been 
rising and confining itself to a definite space in so small a popd : 
and if we suppose some process of change to have developed 
the oil just at the time of the frost, and not before, — this change 
would also be likely to be attended with change of temperature. 
And even then, since oil spreads so quickly, and has so 
transient an effect, and Mr. H.’s hypothesis supposes a wind to 
have prevailed, it appears scarcely to be admitted that it could 
have occasioned that permanent and precisely bounded 
quiescence which his reasoning demands. 
II. 
On the Effects of Twenty Thousand Zinc and Silver Plates, 
arranged as an Electric Column. By Mr. George John 
■Singer, Lecturer on Experimental Philosophy . 
np HE remarkable properties of the Electric Column, in- 
1L vented by Mr. De Luc,* rendered the construction of 
that instrument on an extensive scale a desirable object. Trials 
were previously made on the effect of various methods of com- 
bination, to ascertain the trips t efficient arrangement. That 
which has been here employed consisted’ of two discs of paper 
interposed between each pair of metals 3 one disc being pasted 
to the silver, the other disc unconnected with either metal. 
A series of one thousand pairs of plates thus constructed. 
each 
Philosophical Journal, XXVXL 81 . 
