Conditions of obtaining quantitative measurements--Modification of the block method--Vibration cell--Application of stimulus--Graduation of the intensity of stimulus--Considerations showing that electric response is due to molecular disturbance--Test experiment--Molecular voltaic cell 91 CHAPTER XII INORGANIC RESPONSE--METHOD OF ENSURING CONSISTENT RESULTS Preparation of wire--Effect of single stimulus 100 CHAPTER XIII INORGANIC RESPONSE--MOLECULAR MOBILITY: ITS INFLUENCE ON RESPONSE Effects of molecular inertia--Prolongation of period of recovery by overstrain--Molecular model--Reduction of molecular sluggishness attended by quickened recovery and heightened response--Effect of temperature--Modification of latent period and period of recovery by the action of chemical reagents--Diphasic variation 104 CHAPTER XIV INORGANIC RESPONSE--FATIGUE, STAIRCASE, AND MODIFIED RESPONSE Fatigue in metals--Fatigue under continuous stimulation--Staircase effect--Reversed responses due to molecular modification in nerve and in metal, and their transformation into normal after continuous stimulation--Increased response after continuous stimulation 118 CHAPTER XV INORGANIC RESPONSE--RELATION BETWEEN STIMULUS AND RESPONSE--SUPERPOSITION OF STIMULI Relation between stimulus and response--Magnetic analogue--Increase of response with increasing stimulus--Threshold of response--Superposition of stimuli--Hysteresis 131 CHAPTER XVI INORGANIC RESPONSE--EFFECT OF CHEMICAL REAGENTS Action of chemical reagents--Action of stimulants on metals--Action of depressants on metals--Effect of 'poisons' on metals--Opposite effect of large and small doses 139 CHAPTER XVII ON THE STIMULUS OF LIGHT AND RETINAL CURRENTS Visual impulse: (1) chemical theory; (2) electrical theory--Retinal currents--Normal response positive--Inorganic response under stimulus of light--Typical experiment on the electrical effect induced by light 148 CHAPTER XVIII INORGANIC RESPONSE--INFLUENCE OF VARIOUS CONDITIONS ON THE RESPONSE TO STIMULUS OF LIGHT Effect of temperature--Effect of increasing length of exposure--Relation between intensity of light and magnitude of response--After-oscillation--Abnormal effects: (1) preliminary negative twitch; (2) reversal of response; (3) transient positive twitch on cessation of light; (4) decline and reversal--Resume 158 CHAPTER XIX VISUAL ANALOGUES