SYNOPSIS xxiii 



PAGE 



The Ear : Physiological description Endolymph and perilymph 

 Passage of the impulses The external auditory meatus 

 Malleus, incus and stapes illustrated and described Mechanical 

 impulse questioned Mechanism of hearing far from being 

 satisfactorily settled Neuro-electrical theory more reasonable 

 and probable than chemical or mechanical Proof that it is so 

 The fenestra ovalis Basilar membrane and membrane of 

 Reissner Ear, from external auditory meatus to brain, said to 

 be a telephone system Auditory nerves closed circuits 

 " Faults " and how to test for them - - - 228 



CHAPTER XVII 



ELECTRO-DIAGNOSIS THE GALVANOMETER AND 

 ELECTRODES 



Chief requirements in a galvanometer Its required sensibility and 

 period Illustration of square case Kelvin Its adjustment 

 Its advantages and drawbacks Galvanometers of the d'Arson- 

 val type illustrated Scales illustrated The lamp (illustrated) 

 Types of galvanometer short-circuit keys Shunts Connecting 

 wires Earth connection The electrodes illustrated and de- 

 scribed Sign of current unimportant All deflections 

 comparative - - 234 



CHAPTER XVIII 

 OHM'S LAW 



In its application to the human body Shortly described In terms 

 of hydrostatics Further description Resistance of metallic and 

 liquid conductors Fluctuation of human E.M.F.- 1 Influence of 

 capacity of condenser-ganglion cells Variation of potential 

 Temperature and moisture Diagrams Potential differences - 245 

 The Hand-to-Hand Deflection : Precautions necessary - - 249 



Application of Ohm's Law to Solutions : The researches of Arrhenius - 250 



CHAPTER XIX 



INTERPRETATION OF CERTAIN ELECTRO-PHYSIOLOGICAL 

 PHENOMENA 



Dielectric substances and structures in the human body Effect of 

 heat upon all known dielectrics Formula for calculating the 

 relative resistance of gutta-percha Local temperature and 

 local pyrexia and the effect upon local insulation resistance 

 Maxwell's experiments Heat and liquid conductors Effect of 

 heat upon the dielectrics of the body as compared with its effect 



