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ELECTRICAL STIMULUS AND RESPONSE. 



Response in the Living and Non-Living. By Jagadis 

 Chunder Bose, M.A. (Cantab.), D.Sc. (Lond.). Pp. 

 xix + 199 ; with illustrations. (London : Longmans, 

 Green and Co., 1902.) Price icxy. 6d. 

 'HE apparent aim of this book is to show that 

 "living response in all its diverse manifestations 

 is found to be only a repetition of responses seen in the 

 inorganic" (p. 189). It is difficult to treat this conclu- 

 sion seriously, and the difficulty is sensibly increased by 

 the mental bewilderment which is experienced on reading 

 such statements as the following : — 



"From a confusion of 'dead' things with inanimate 

 imtter it has been tacitly assumed that inorganic sub- 

 stances, like dead animal tissues, must necessarily be 

 irresponsive, or incapable of being excited by stimulus — 

 an assumption which has been shown to be gratuitous " 

 (p. 181). 



The conclusion which we are compelled to draw from 

 this quotation is that Prof.Bose doesnot regard dead things 

 as inanimate matter, and if this be the case, it may seem 

 superfluous to offer any extended criticism of those por- 

 tions of the book which set forth the experimental 

 grounds for such beliefs. It is, however, very desirable 

 that discredit should not be thrown upon the use of 

 fruitful methods of investigation well known to physio- 

 logists in consequence of the fallacious character of the 

 author's conclusions ; moreover, the experiments upon 

 which he rests his case are set forth in a somewhat con- 

 vincing manner, and the book may with the aid of 

 copious illustrations achieve some popularity. , 



The experimental facts brought forward comprise, (1) 

 some limited aspects of the changes occurring in 

 muscles, nerves and plants when subjected to particular 

 modes of stimulation, and (2) some electrolytic effects 

 occurring when moist conductors are brought into con- 

 tact with metallic surfaces and the latter are caused to 

 vibrate. It is on the strength of a superficial resem- 

 blance between the electromotive changes observed in 

 these two groups that the author makes his astounding 

 generalisations. The phenomena of muscle and nerve 

 brought forward are taken from various physiological 

 works, and the particular response selected is that of the 

 familiar excitatory electromotive change ; it is, however, 

 very inadequately treated, as no reference is made to the 

 classical researches of Du Bois-Reymond, Hermann, 

 Bernstein, Hering, Burdon Sanderson and others. 



In consequence of the author's limited survey of the 

 subject, he has fallen into an error of quite an elementary 

 nature in his description of the muscular response. He 

 appears to think that the superficial resemblance between 

 the change of form which muscle undergoes in contraction 

 and the swing of a galvanometer needle when de- 

 flected by the sum of the electrical currents present in 

 tf-tanised muscle affords sufficient ground for the state- 

 ment that " it is found that the electrical and mechanical 

 records are practically identical " (p. 12). This identity can 



NO. I/40, VOL. 67] 



only refer to the time relations of the two classes of events, 

 and it has been known for half a century that the elec- 

 trical and mechanical responses do not run the same 

 course. The results obtained by the physiological 

 rheoscope, the repeating rheotome, the telephone and 

 the capillary electrometer (all disregarded by the author) 

 afford convincing proof that whereas the change of form 

 during so-called tetanus is sustained by the fusion of the 

 successive mechanical responses, the electrical disturb- 

 ances are not so fused, but constitute a rhythmical series 

 of distinct states. The time relations of the muscular 

 twitch evoked by a single stimulus reveal the reason for 

 this want of parallelism, since the electrical response has 

 both culminated and subsided before the mechanical one 

 has been completed. The author having thus disregarded 

 the most fundamental characters of muscular and 

 nervous responses, i.e. their time relations, it is clear that 

 no sweeping generalisations involving these responses 

 are justifiable. 



In treating the vegetable tissues, the author has 

 selected as a typical response an electrical change 

 which occurs in portions of plants which have been 

 subjected to sudden mechanical strain (torsion, &c). 

 The displacement caused by the strain is associated 

 with a difference of electrical potential in the part pri- 

 marily affected as compared with other parts situated 

 in more remote, and thus less disturbed, regions. 

 These electrical alterations are of considerable interest, 

 and attention has been drawn to their existence by 

 Waller, who has pointed out their local character. The 

 local character of the electromotive effect has its counter- 

 part in animal tissues, but it is not characteristic of those 

 particular animal responses which are selected by the 

 author for the purpose of comparison, since these are 

 propagated from the seat of stimulation along the proto- 

 plasmic continuum of the muscle or the nerve fibres. 

 Propagated effects of this type can be found in certain 

 plant tissues — for instance, Dionasa — but the plant re- 

 sponses described by Prof. Bose do not include these. 

 It follows, therefore, that such comparisons as the author 

 is able to make do not warrant the sweeping statement 

 that 



"a complete parallelism may be held to have been 

 established between plant response on the one hand 

 and that of animal tissue on the other " (p. 80). 



Some curious chapters in the book deal with a novel 

 "response in metals." This was generally obtained by 

 connecting a strip of metal (tin, platinum, &c) with 

 moist conductors, which in their turn were connected 

 with a galvanometer through non-polarisable junctions ; 

 the sudden jar of a blow was the so-called stimulus, and 

 the alterations caused by the shatter in the polarisation 

 interfaces appear to constitute the so-called electrical 

 response. The observations are brought forward by 

 Prof. Bose, not so much for any intrinsic physical interest 

 they may possess, as for the purpose of showing how far 

 they are susceptible of modification under conditions 

 which, in his opinion, also modify the electromotive 

 phenomena of living tissues and thus of serving as a 

 support for his speculations. The language employed in 

 their description is often of a singular character ; thus 



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