120 Papers relating to the Fasion. of Carbow. 
and vigorous limbs—sawing it into cylinders of convenient » 
size, and igniting it thoroughly, ina blaek lead pot,* covered 
by another of the same kind—the whole being placed in a 
powerful wind furnace. Other pieces of the same kind of 
charcoal were treated in the same manner, after being pre- 
viously boiled in distilled water, or in diluted muriatie acid, 
the object of which obviousiy was to remove alkaline, fer- 
ruginous. or other soluble impurities. | may observe, once 
for all. that there appeared to be no difference in the sensi- 
ble phenomena attending the experiments or in the results, 
whether one kind of charcoal or another was-employed, or 
whether it had been boiled with acids and water or not : af- 
terboiling, it was always oar Nest in the — — it 
was uséd in the deflagr 
A leading object of ren sepeieetite now to be ‘stated. was 
to ascertain whether there was any change of weight in the 
ignited charcoal. 
March 4th, 1825, bgiediie being used, which had been 
boiled in mente muriatic acid, afterwards in slistitied water, 
and finally. ignited anal in close vessels i nieces 
gett HII 
I ought perhaps: to mention: that the dotigintet poche 
had been enlarged by the addition of eighty of the 
; nd coils suspended on two parallel beams and dip- 
ping into their appropriate troughs ; thus the surface of metal 
was doubled, and the power of the instrument very consid- 
erably increased. No difference however was observed itt 
the phenomena, except in the rapidity and energy with which 
they were produced. It should also be observed that the 
word positive here refers to the zinc, and the word negative 
to the copper pole. These terms ‘having been erroneously 
applied, when the instrument was first invented, and the error 
not being discovered until after my former experiments were 
petted: the designation of the poles is therefore oppo- 
site, in these remarks, to that employed in the former papers. 
1, The points of charcoal were instantly fused, with a 
—— of the charcoal, the result exactly resembling he- 
te—the projecting cone or cylinder being formed rapidly 
on the negative, while a ene oes cavity was po 1 
the positive charcoal. 
@oThe same. 
Sie vert ; A fey Ey cut Be peed 
* No sand was used to cover the pieces, 
