( 133 ) 



ration is waiitiug and gives place to an enormous acceleration of the 

 superficial respiration (^see fig. XII). Sometimes there is a form 

 intermediate between the two (see fig. XIII'. 



Sumraa summarum. During the exertion the respiration, specially 

 the expiration, is shorter and more siqjerficial ; both inspiration and 

 expiration are diminished in the beginning, but give gradually uay 

 to a stronger position of inspiration of the thorax. Then a compen- 

 satory retardation of respiration follows^ specially of the expiration, 

 with an inclination toirards more extensive expiration and longer 

 intervals. 



During such a sum, however, the lumen of the periferie blood- 

 vessels changes also. Halliox and Comte have invented a simple 

 instrument to register the volume of the fingers, the so-called capil- 

 lary pulse of the fingers. A caoutchouc cylinder is placed firmly 

 along the fingers in the hollow of the hand, while the whole hand 

 is covered by a solid glove. Every change in the volume of the 

 fingers under the influence of the working of the heart or the respi- 

 ration, is imparted to the caoutchouc and can be registered. 



And now, just as Bixet and Courtier have already pointed out, 

 it ap[ieared also to me, that sometimes after a preceding extension, 

 the volume of the fingers decreases during the sum (see fig. XV). 



BiSET and Courtier think rightly, that this is partly the con- 

 sequence of a spasm of the blood-vessels in the fingers. In fact, 

 when we try to find out with Mosso's sphygmomanometer, as they 

 also did, how it is with the blood-pressure in the capillaria, the 

 result is, that the pressure of the blood increases in the capillaria 

 during the sum. 



If according to the particular arrangement of this instrument we 

 start from a very slight opposing pressure (in casu 30 mM. Hg.), a 

 curve is traced during the sum, which does not only ascend, but 

 shows increasing deviations (see fig. XYI0) ; and if we start from the 

 optimum of the opposing pressure (in casu for myself ± 50mM. Hg.) 

 the tracing rises, while the deviations decrease (fig. XVK). 



So the volume of the finger becomes smaller, the pressure in 

 its small blood- vessels increases. There is undoubtedly a spasm 

 of the vessels in the perifery. Besides the spasm of the vessels 

 another influence works on the volume of the fingers. The deep 

 inspiration empties the blood-vessels and has certainly some in- 

 fluence on the descending of the curve which the volume of the 

 fingers traces during the sum. In the third place it is not impossible 

 that in tiie arrangement of the experiment as done bv IlALLloy and 



10 

 Proceedings Royal Acavl. Amsterdam. Vol. I. 



