CHAP. II. 



OF THE FORCE EVOLVED DURING CHEMICAl ACTION : 

 FIRST, IN THE VOLTAIC CIRCLE ; SECONDLY, IN THE 

 REACTION OF DIFFERENT SOLTTTIONS UPON EACH 



OTHER. OF DIFFERENTIAL CURRENTS. OF COMBINED 



CURRENTS. — THE FOEOE, A POLAR FORCE, AND ITS 

 DEFINITION. 



As the facts connected with the developement of 

 electrical action in the living body are so intimately- 

 related to those which occur during ordinary 

 chemical action, I shall in the present chapter 

 confine my observations chiefly to the developement 

 of electricity under these circumstances, and speak, 

 first, of the electric power, or force, as it exists in 

 the voltaic circle ; and, secondly, of the power as it 

 exists during ordinary chemical action — during the 

 reaction of different chemical solutions upon each 

 other. 



First : Of the force as it exists in the voltaic circle. 

 The form which electricity assumes in the voltaic 

 circle, and termed current force, is an indisputable 

 fact, granted both by the contact as weU as by the 

 chemical theorists. As the mass of evidence in 

 favour of the chemical origin of the power in the 

 circle preponderates over that of the contact theory. 



