62 Notices respecting New Books. 
description invelves considerable practical information on the 
means of conducting such experiments, The following is a 
simple means of reviving metals from their oxides : 
‘¢ Introduce some oxide of tin into a glass tube, so that when 
the tube is laid horizontally the oxide may cover about half an 
inch of its lower internal surface. Place the tube on the table 
of the universal discharger, and introduce the pointed wires in- 
to its opposite ends, that the portion of oxide niay lie between 
them. Pass several strong charges in succession through the 
tube, replacing the oxide in its situation, should it be dispersed. 
If the charges are sufficiently powerful, a part of the tube will 
soon be stained with metallic tin, which has been revived by the 
action of the transmitted electricity. 
The decomposition of water and the action of electricity on 
different gases are also fully described, and are accompanied by 
a table of the results of electrifying mixed gases ; and another on 
the action of electricity on compound gases. On the causes of 
these phenomena, which the author does not attempt to ex- 
plain, he has the following observations : 
*¢ These various effects produced by the same ageney do not 
appear susceptible of any other explanation than that which as- 
sumes the action of electricity to be mechanical; and even on 
this assumption they are not strictly intelligible. ‘The momen- 
tary agitation into which the various mediums are thrown by 
the action of the spark, might be considered as likely to pro- 
mote a new arrangement of parts; but, admitting this, why is 
the change instantaneous in some instances, and gradual in 
others? And by what inversion of principle is the same impulse 
that unites the particles of bodies, enabled subsequently to se- 
parate them? These are questions it would be interesting to 
resolve ; but there appears no clue by which such intricate pro- 
cesses can be at present analysed. The chemist must therefore 
be content to avail himself of the practical advantages they af- 
ford to his art, and await the progress of discovery for the de- 
velopment of their theoretical relations.” 
An enumeration of the bodies which are rendered phospho- 
rescent by electricity, with remarks on that singular phenomenon, 
and a sketch of the magnetic effects of electricity, close this part 
of the work, which the chemical student will find a very in- 
teresting and instructive exercise. _ 
[To be continued. ] 
Mr. William Phillips has in the press, An Elementary Intro- 
duction to the Knowledge of Mineralogy and of Minerals; in- 
eluding some account of the places at which, and of the circum- 
stances under which, minerals are found; and explanations of 
the 
