Galvanic Deflagrator. . 15 
ment, during a certain period, rather gains than loses strength, 
by the raising of the coils. It seems as if the imponderable fluids, 
partially exhausted from it by its continued action, had time 
again to flow in from surrounding objects, and thus to impart 
new energy. I found the power of the instrument to last for se- 
veral days, although declining, and the same charcoal points, 
when well prepared *, would also continue to operate for several 
days. _ When the coils, after immersion, had been suspended, for 
some hours, in the air, a coating of green oxide or carbonate of 
copper always formed on one part of the outside of the copper 
coils, and on the same part in all, but no where else. If I do 
not misremember, it collected next to the negative pole, but was, 
of course, always removed by the next immersion, though it was 
formed again at the next suspension. 
One circumstance occurred during these experiments, which 
demands further attention. 
In the hope of uniting the power of vour Deflagrator with 
that of the common galvanic battery, I connected your instru- 
ment with the powerful one mentioned above. Both instruments, 
when separately used, acted at the time, with great energy, pro- 
ducing both their appropriate and common effects, in a very de- 
cided manner ; but, on connecting by the proper poles, the bat- 
tery of six hundred and twenty pairs, with the Deflagrator of 
eighty coils, | was greatly surprised and disappointed, at finding 
the power of both instruments so completely paralysed, that, at 
the points where a moment before, and when separate, a stream 
of light and heat, hardly to be endured by the eye, was poured 
forth—now, when connected, both instruments could scarcely 
produce the minutest spark. On separating the instruments, 
they both resumed their activity; on again connecting them, it 
was again destroyed, and so on, as often as the experiment was 
made. While they were iv connexion, provided the coils were 
lifted out of the acid, so as to hang in the air merely, then the 
power of the common galvanic battery would pass through the 
Deflagrator, which appeared to act simply as a conductor; and, as 
might have been expected when so extensive a conductor was 
used, the power of the common battery was, in this case, con- 
siderably diminished, while that of the Deflagrator did not act 
at all. 
If, while things were in this situation, the coils of the Defla- 
grator, without being plunged, were lowered so far as merely to 
dip their inferior extremities say only one-fourth of an inch in 
the acid, the communication was immediately arrested, and all 
effect destroyed almost as completely as when the coils were 
wholly immersed. Thus it appears that the inability to act, in 
* By igniting pieces of mahogany beneath sand inacrucible, 
P2 connexion 
