28 Art. 1.— K. Fuji : 



;it present to use siicli nii iiistruiiient ms tlie eapillary electrometer 

 or tlie string galvanometer. As we remarked at tlie beginning of 

 tins paper, snch an instrument does not give a true picture of the 

 electromotive force as in this case, unless the change of the 

 electromotive force is very slow as in a cardiogram. Some people 

 tr}^ to correct the curve obtained (»n these instruments by finding 

 the inclination of the tangent to the curve from point to point. 

 But since a small error in the measurement of the inclination may 

 cause a considera])ly great error in the correction, especially when 



tlie inclination approaches -y, it is dangerous to rely on the 



result obtained by analysing the curve thus corrected, even if it be 

 allowed that the ])rinciple of tbe correction is right. On the 

 contrary, tlie electromotive force of the discharge of an electric 

 organ is very lai'ge and therefore in this case we may employ such 

 an ingenious instrument as the oscillograph, in which, if used with 

 proper care, correction is unnecessary. ]\Ioreover the stimulus must 

 be very sti-ong for exciting the organ so that even a subminimal 

 stimulus may be recorded by the same insti'ument. It must, 

 however, be admitted that the record due to the abrupt change of 

 current is not so correct as that of the discharge. The only 

 diflficulty met with was our local trouble in obtaining lisli. 



lieturning to the problem: we made many experiments 

 regarding tlie magnitude of the electric stimulus and the same of 

 the corresponding discliarge. The experiments were made in the 

 main with direct stimulation, and its form was that described in 

 § III. As it Avas morj convenient to make the picture of the 

 stimulus on the oscillogram on the same side of the zero line as 

 that of the discharge, the direction of the stimulating current was 

 always homodrome. By changing the strength of the current of 

 the primary of the induction coil, or by shifting the position of the 

 circuit-breaker with regard to that of the connection-changer on the 

 stimulation-apparatus, stimuli having different strengths and equal 

 durations, or stimuli having different durations and equal strengths, 

 were given to the organ and the resulting discharges were in- 

 vestigated. 



