Conditions for obtaining electric response--Method of injury--Current of injury--Injured end, cuproid: uninjured, zincoid--Current of response in nerve from more excited to less excited--Difficulties of present nomenclature--Electric recorder--Two types of response, positive and negative--Universal applicability of electric mode of response--Electric response a measure of physiological activity--Electric response in plants 5 CHAPTER III ELECTRIC RESPONSE IN PLANTS--METHOD OF NEGATIVE VARIATION Negative variation--Response recorder--Photographic recorder--Compensator--Means of graduating intensity of stimulus--Spring-tapper and torsional vibrator--Intensity of stimulus dependent on amplitude of vibration--Effectiveness of stimulus dependent on rapidity also 17 CHAPTER IV ELECTRIC RESPONSE IN PLANTS--BLOCK METHOD Method of block--Advantages of block method--Plant response a physiological phenomenon--Abolition of response by anaesthetics and poisons--Abolition of response when plant is killed by hot water 27 CHAPTER V PLANT RESPONSE--ON THE EFFECTS OF SINGLE STIMULUS AND OF SUPERPOSED STIMULI Effect of single stimulus--Superposition of stimuli--Additive effect--Staircase effect--Fatigue--No fatigue when sufficient interval between stimuli--Apparent fatigue when stimulation frequency is increased--Fatigue under continuous stimulation 35 CHAPTER VI PLANT RESPONSE--ON DIPHASIC VARIATION Diphasic variation--Positive after-effect and positive response--Radial E.M. variation 44 CHAPTER VII PLANT RESPONSE--ON THE RELATION BETWEEN STIMULUS AND RESPONSE Increased response with increasing stimulus--Apparent diminution of response with excessively strong stimulus 51 CHAPTER VIII PLANT RESPONSE--ON THE INFLUENCE OF TEMPERATURE Effect of very low temperature--Influence of high temperature--Determination of death-point--Increased response as after-effect of temperature variation--Death of plant and abolition of response by the action of steam 59 CHAPTER IX PLANT RESPONSE--EFFECT OF ANAESTHETICS AND POISONS Effect of anaesthetics, a test of vital character of response--Effect of chloroform--Effect of chloral--Effect of formalin--Method in which response is unaffected by variation of resistance--Advantage of block method--Effect of dose 71 CHAPTER X RESPONSE IN METALS Is response found in inorganic substances?--Experiment on tin, block method--Anomalies of existing terminology--Response by method of depression--Response by method of exaltation 81 CHAPTER XI INORGANIC RESPONSE--MODIFIED APPARATUS TO EXHIBIT RESPONSE IN METALS