OF GALVANIC ELECTUICTV. 



the electrical states of their atoms, or of these fluids during" their continuous circulation 

 through them. 



The excitement of electricity by means of friction, by compression, by the fusion of 

 inflammable bodies, by evaporation, by the disengagement of gas, by the disruption of 

 a solid body, by the contact of dissimilar substances, and lastly by chemical decomposi- 

 tion all combine in establishing- the intimate connexion for which we contend. 



Whenever bodies, brought by artificial means into high states of opposite electricit;-, 

 are allowed to restore the electricity ; heat and light are the consequences. [Davy.] 



These effects takes place in the same manner if performed in a vacuum. The light 

 produced in this manner appears from the experiments which have been related, to be of 

 the same nature with the solar beam, and to be divisible into the prismatic colours. The 

 light exhibited by phosphorescent bodies, and by matter under its various conditions, 

 gives similar results. Therefore, from taking a survey of the electrical phenomena, of 

 those displayed by chemical combinations, and of other manifestations of nature, v/e 

 are inclined'to adopt the belief that light and caloric (as they exist in the solar rays, and 

 as they are otherwise produced) are the result of the combination and neutralization of 

 the opposite electricities, whether taking place in a direct manner, and in their free 

 state of existence, or through the medium of the particles of matter which they endow; 

 light being more or less perfect according as the netralization is more or less complete, 

 and the caloric resulting from the intensity of their action. 



Before leaving the consideration of the action of the electric fluids upon each other, 

 and upon the molecules of matter, it is necessary to remark respecting a property which 

 the molecules of matter appear to possess under certain circumstances, of arranging 1 

 themselves in definite directions ; this has generally been called the polarization of 

 matter a phenomenon observed in the crystallization of numerous substances, and in 

 different chemical actions. The polarization of the atoms of matter seems to result 

 from the electrical states which they acquire from the electricities circulating around 

 them, and to arise from a property with which the electricities are themselves endowed, 

 or from their mutual action independently of their connexion with the molecules of 

 matter. According to this view of the subject, we should be led to expect, that the 

 electricities, as they exist in the solar beam, unconnected with matter, would give rise 

 to the phenomenon of polarization, in a similar manner as when their action is ex- 



igencies and the mag- 

 netical attractions, is a subject which has lately interested scientific inquirers through- 

 out Europe. It would almost seem, from their observations, that manifestations of ths- 

 magnetic power result from the electrized state of the atoms of the magnet, and their 

 cpnsequent polarization; and, from the continuous circulation of the electric fluids 

 either through its substance or upon its surface*. 



Since the discoveiy of Galvarii, several physiologists have attempted to explain the 

 phenomena of the animal world, by imputing the functions of the nervous system to 

 the electro-motive energy, generated or developed by the cerebro-spinal masses, 

 Amongst those who have espoused this opinion we may mention Sprengel, Reil, Pro- 

 chaska, Wilson, Philip, Lenhossek, &c. There can be no doubt that the electricities 

 circulate through animal bodies in different conditions, and give rise to subordinate of' 

 fices in the animal economy, under the superior dominion of a vital influence ; and 

 moreover, that they (or one of them at least) are of a stimulus to to this influence. 

 The experiments of the physiologists just named, especially those of Dr. Philip show 

 this, but nothing more than this. They refer to the electrical apparatus which certain 

 fishes possess, and the power they have of giving electrical shocks in farther proof of 

 the justness of their inference ; but it may be asked, if the nervous influence be the 

 same as electricity, why should these animals possess an apparatus distinct from the 

 nervous system, and under its control, for the production otthe electrical phenomena ? 

 The existence of this apparatus confirms the proposition we have just now stated ; 



* In the annual oration delivered to the Medical Society of London in 1822, we en- 

 deavoured to show that the phenomena of attraction or gravitation, chemical affinity, 

 combustion, chrystillization, magnetism, light and heat, (both as they exist in the solar 

 rays, and as they are otherwise produced,) in short, that all the phenomena of the in- 

 organized world and of the solar systems may be explained by means of the agency of 

 two universally diffused electricities. 



