o^ Art. 1.— K. Fuji : 



discharge increases very slowly from zero. Then comes a steep 

 increase of the height of the discharge, where the curve has an in- 

 flexion point and then becomes concave with respect to the axis of 

 the abscissa. By direct stimulations we could not arrive at the 

 upper part of the curve on account of the ^'cry large stimulation 

 current required. Nevertheless, it is very probable that the curve 

 approaches an asymptotic value of the ordinate wliich may easily be 

 attained in the case of indirect stimulation. Thus the curve 

 forms an S-shape analogous to that, found by Waller, relating to 

 the negative variation in, the nerve. Here we may remark that it 

 is very doubtful whether the words minimal und subminimal stimidus 

 as customarily used have any definite meaning. B,y the Avord 

 (minimal stimulus or liminal current, is certainly meant the stimulus 

 by which the response becomes just sensitive to a certain in- 

 strument. Of course, if Ave acknoAvledge the truth of the ' ' all or 

 none " theory, there certainly exist the minimal and the maximal 

 stimulus in the literal meaning. But that Avhich is ordinarily 

 obtained by experiment Avould not be the true minimal stimulus, 

 i. e. not for the response of a unit element. Noav, if Ave take the 

 height of the discharge as a measure of the excitation, the 

 proportionality between the current and the response in Hoor- 

 Aveg's formula does not hold good for the finite range of the 

 discharge. It is not clear whether the inclination of the tangent 

 to the curve at the origin is equal to zero or not. If the latter is 

 the case, the proportionality in the.ver}^ small portion at the 

 beginning of the curve, in agreement Avith the formula of Hoorweg, 

 is nothing but the general property of any curve, that a small 

 portion of it may be regarded as a straight line. ■Many trials Avere 

 made to formulate the relation extending to the finite region of 

 the stimulus, but the results Avere not satisfactory. As Ave re- 

 marked before, if aa^c may assume that the magnitude of a discharge 

 is due to the number of elements evoked by the stimulus, and that 

 the number depends on the A'^ariety of the elementary portions 

 Avhose minimal stimuli are different from one another, then the 

 curA^e representing the relation betAveen the strength of the stimulus 

 and the area of the discharge should be the integral curve of the 



