170 Galvanic Batteries. 
MISCELLANIES. 
DOMESTIC AND FOREIGN. 
1. Mr. Faraday on the most improved form of the Galvanic De- 
flagrator, especially as constructed by Dr. Hare.—More than sixteen 
years havé elapsed since an account was given in this Journal by Dr. 
Hare of his galvanic deflagrators, and of their great power in pro- 
portion to their size in producing intense ignition. Not Jong after, 
the experiments of Dr. Hare were with some additions repeated by 
us, and the results fully confirming the allegations of the inventor 
were also published in this work. Although Dr. Hare’s memoirs 
and ours with engravings were published in the Annals of Philoso- 
phy and Philosophical Magazine, London, yet it does not appear 
that his deflagrators were imitated in Europe, the old and inferior 
constructions continuing in general use. It is satisfactory to find 
from the following abstracts from a paper of Mr. Faraday, that the 
course of his investigations has led him latterly to consider the defla- 
grator of our countryman as the most efficient form of a galvanic 
series. We quote those passages of Mr. Faraday’s paper on the 
subject of the deflagrator which tend to justify our statement. 
Alluding to the principles which this distinguished author had con- 
sidered as established by his investigations, he uses the following 
language. 
“Guided by these principles, I was led to the construction of a 
voltaic trough in which the coppers assing round both surfaces of 
the zines as in Wollaston’s construction s 
new trough was in all essential respects the same as that invented an 
described by Dr. Hare, Professor in the University of Pennsylvania, 
to whom I have great pleasure in referring it. 
“Dr. Hare has fully described his trongh.* In it the contiguous 
copper plates are separated by thin veneers of wood, and the acid is 
on to or off the plates by a quarter revolution of an axis, to 
* Philosoph. Magazine, 1824, Vol. uxim. p. 271, or Silliman’s Journal, Vol. vil. 
See also a previous paper by Dr. Hare, Annals of Philosophy, [second series,] 
1821, Vol. 1, p. 329, Also Phil. Mag. [first series,] Vol. vir. p. 289, in which he 
speaks of the non necessity of insulation between the coppers. 
