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fibre, and in this way conducted towards the end arborization, where 
a new nervecell is exposed to a temporary electrical P. D. procuring 
an adequate stimulus for that cell; here the same fact will repeat 
itself, we obtain again a potential-wave, extending along the second 
neurone. If a lower motor neurone were stimulated, then too a 
potential-wave would extend itself along the nerve-fibre, to pass 
finally on to the muscle-protoplasma, where the stimulus is transformed 
into potential energy, which in this case however would be 
a contraction. 
It is sufficiently known, that by increasing the stimulus the effect 
increases too, but as to the exact relation between the two magnitudes 
—cause and effect — we are in ignorance as yet. A law does exist 
concerning a definite kind of stimuli, acting upon some of our senses; 
a law indicating approximately in what manner the intensity of 
sensation increases with the magnitude of sense-stimulation — the 
well-known psycho-physical law of WeBeER—FrCHNER. This law 
however decidedly does not prevail for the stimulation of contractile 
‘substanee: the endeavour of PREYER to establish a myophysical law, 
quite analogous to the psycho-physical law is to be considered as 
a failure '). : 
Apart from the above mentioned treatise of Preyer, which may 
be safely left out of consideration, together with the objections raised 
against it by LUCHSINGER *) and BERNSTEIN *), a few other commu- 
nications have been published concerning the subject occupying us here. 
Among the first publications on this matter ranks that of HERMANN *), 
who in i861 loaded a muscle with different weights and measured 
the intensity of the smallest stimulus, sufficient to cause a minimum 
contraction. The results of these researches are rendered clearly 
enough by his words: „Es ergab sich, dasz bei gleichmässigem 
»Wachsthum der verlangten Energie die Reizgrössen anfangs langsam, 
„dann schneller wachsen und bald nicht mehr erreicht werden. Mit 
„anderen Worten : bei gleichmässig zunehmenden Reizgrössen wachsen 
„die Energien zuerst schnell, dann immer langsamer und erreichen 
„bald ein Maximum (die sog. „absolute Kraft’’).” 
I wish to claim attention for the fact that the conclusion thus put 
before us is substantially a right one, but — as has been demonstrated 
1) W. Preyer, Das myophysische Gesetz. Jena 1879. 
2) LucasiNGer, Archiv f. Physiologie. VI. 8. 295, 642. VIII. S. 538. 
*) BERNSTEIN, " 1 " VI. 8. 403. VIL. S. 90. 
*) HERMANN, Archiv f. Anatomie u. Physiologie. 1861. 8. 369—396. Id., Hand- 
buch d. Physiologie. I. 1. S. 108. 1879. 
