(3(5 Art. 1.— K. Fuji : 



tion ()1 the 8tiinulatiiig current was in general descending on 

 closing tlie primary circuit. But in one case the ascending and 

 the descending stimuli were alternately gi\'en to the nerve by a 

 proper contrivance on the shaft of the registering ch-u m (Plate IV., 

 Fig 3). In another case the stimuli were given directly to tlie 

 organ. Here, as remarked at the outset of this paper, the in(hic- 

 tion coil must be excluded from the circuit during the dis- 

 charge of the organ. This was accomplished by a proper contri- 

 vance lielonging to the shaft of the registering drum (Plate IV., 



Fig- '^) . . . 



Beginning with the former case, the fatigue curve resembles 



very closely that of muscle. Oscillograms No. 1, No. 2 (Plate 

 XXIV.), No. 3, No. 4 and No. 5 (Plate XXV.) show such curves. 

 In No. 1, which shows the typical form of the fatigue curve, the 

 electromotive force increases a little during a few discharges at the 

 outset of the fatigue, and passing over a maximum, it decreases 

 almost exponentially. The rate of decrease increases after pass- 

 ing the maximum, then decreases gradually, again increases 

 a little an<l then decreases again. Thus repeating the same 

 type of variation, in such a way that the locus of the top of the 

 discharge curve forms a mild wave form, the nerve or the organ is 

 tired out. Two low loci on the Ijottom of the oscillogram are 

 those of the secondary and of the tertiary discharge. The marks 

 of regular intervals on the bottom ai'e those of a second. Here 

 we may remark that the tops of the discharge curves form a 

 smooth curve at the beginning of the fatigue, but when in deep 

 fatigue their lieights become very irregular (Oscillogram No. 2). 



Oscillograms No. 3, No. 4 and No. 5 (Plate XXV.) form a 

 series of experiments. Oscillogram No. 4 was taken at an interval 

 of one hour after No. 3, and Oscillogram No. 5 at 40 min. after No. 4. 

 The number of stimuli is about 25 per sec. Here we see, that the 

 fatigue may be partially recovered by a repose of the stimulation 

 so that there must be two kinds of fatigue, namely that which can 

 be recovered and that which cannot be recovered. I am of 

 opinion that, that part of the fatigue which can be recovered is 

 the same as the temporary fatigue of tlie nerve discussed in the 



