by Jagadis Bose
210 pages
ISBN: 9780980297690
US $14.95 UK 10.95 GBP
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At one stage of his long career, Sir Jagadis Chunder Bose undertook an examination of inorganic matter in the same way as a biologist examines a muscle or a nerve.
He subjected metals to various kinds of stimulus—mechanical, thermal, chemical, and electrical. He found that all sorts of stimulus produce an excitatory change in them. This excitation sometimes expresses itself in a visible change of form, and sometimes not; but the disturbance produced by the stimulus always exhibits itself as an electric response.
He next subjected plants and animal tissues to various kinds of stimulus and found that they also give an electric response. Finding that a universal reaction brought together metals, plants and animals under a common law, he next proceeded to a study of modifications in response, which occur under various conditions. He found that they are all benumbed by cold, intoxicated by alcohol, wearied by excessive work, stupefied by anaesthetics, excited by electric currents, stung by physical blows and killed by poison—they all exhibit essentially the same phenomena of fatigue and depression, together with possibilities of recovery and of exaltation, yet also that of permanent irresponsiveness which is associated with death—they all are responsive or irresponsive under the same conditions and in the same manner.
His investigations showed that, in the entire range of response phenomena (regardless of whether the subject is metallic, plant or animal in origin) there is no breach of continuity; that “the living response in all its diverse modifications is only a repetition of responses seen in the inorganic” and that the phenomena of response “are determined, not by the play of an unknowable and arbitrary vital force, but by the working of laws that know no change, acting equally and uniformly throughout the organic and inorganic matter.”
CONTENTS
1 / The mechanical response of living substances
Mechanical response – Different kinds of stimuli
–Myograph – Characteristics of response curve: period,
amplitude, form – Modification of response curves
2 / Electric response
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
3 / 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
4 / Electric response in plants – block method
Method of block – Advantages of block method – Plant
response a physiological phenomenon – Abolition of
response by anæsthetics and poisons – Abolition of response
when plant is killed by hot water
5 / 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
6 / Plant response – on diphasic variation
Diphasic variation – Positive after-effect and positive
response – Radial E.M. variation
7 / Plant response – on the relation between stimulus and response
Increased response with increasing stimulus – Apparent
diminution of response with excessively strong stimulus
8 / 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
9 / Plant response – effect of anæsthetics and poisons
Effect of anæsthetics, 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
10 / 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
11 / Inorganic response – modified apparatus to exhibit response in metals
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
12 / Inorganic response – method of ensuring consistent results
Preparation of wire – Effect of single stimulus
13 / 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
14 / 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
15 / 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
16 / 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
17 / 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
18 / 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 – Résumé
19 / Visual analogues
Effect of light of short duration – After-oscillation – Positive
and negative after-images – Binocular alternation of vision
– Period of alternation modified by physical condition
– After-images and their revival – Unconscious visual
impression.
20 / General Survey and Conclusion
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