258 



I) K S C 11 I !• T I <) N or T II i: I' I' A T H S. 



Fig. 3.— Traciiij; of Kxi.uriiiioiil 107, p. 1&4. This IraciiiK sliows the effect of galvuiiiziiig the Bciotic 

 uiTvu ttflor acsiruciiuii of liio lliuigV ngioii of tin- lifuiii curlcx, siclioii ol llic vugi uiid ol iho 

 Hplonibuics just above llair iiuruiicc to ilic diuplirugiu | cururuulioii uiid uriiliciui ri>piruliuu 

 Luviiig bvvu prai-titivd. 



Fig. li— . ruiiiigB uf ExpiTiuiciil los, p. 1;>4. lii iliiw figure there arc two traeiiigs with one abscisjia 

 uud one beeoud line. The upper Irutiiig was made lirhl, after division uf the pur vugum, and 

 of the splanchnics ju8t alwvc the diaphragm. The first -\- bejongn to this upper tracing and 

 marks where the galviiiiic irritation of the .seialic nerve commenced ; this irritation wan conlinmd 

 25 seconds. Tlie lower tracing wa.s made later, from the same dog, after section of par vagiim 

 and gplanchnics as dcPcribed, and also destruction of Ilitzig's region of the cerebral cortex. 

 The second + marks where the galvanic current was applied to the sciatic of the same strength 

 us ill ilie fir.-'l tracing. 



PLATE IV. 



Fig. 1.— Tracing of Experiment 101, p. 147. The sitlunchnics had been entirely severed jn.'it above 

 the diaphragm, also the vagi in the neck. C'urari hud been given ami artificial respiration was 

 practised. The lower straight line is the abscis!<a : irritation was applied by means of a 

 powerful galvanic current to the sciatic nerve, ot the point where the curve begins to rise, and 

 was removed just before the tracing begins to drop. 



Fig. 3.— Tracing of Kxperiment lOH, p. 154. This tracing represents the effect upon the arterial 

 pressure of interrupting the respiration at 1 minute, 34 seconds of the P^xpcriment. The 

 interruption lasted 8 seconds. 



Fig. 3. — Tracing of K.xperiinent 1()0, p. 1 U). This tracing shows effect of galvanic irritation of the 

 sciatic nerve, after section of the .splanchnics just above the diaphragm and of the par vugum 

 in the neck, curarization and artificial respiration being practised. S represent:* conimenccuieut 

 of irritation. O its cessation. 



Fig. 4. Tracing of Experiment OS, p. 145 The .splanchnics had been cut above the diajihrngm, the 

 right |io8sibly not having been entirely severed. At I a jiowcrful current was applied to the 

 sciatic nerve ; at O irritation ceased. The vagi had been divided, and curari given : artificial 

 respiratiou was applied throughout. 



1M,ATK V. 



In this plate, Fig. 1 and Fig. 2 arc parts of one experiment (109, page 150), both having been 

 made upon one drum and having the same abscissa and second-murker line. Fig. 1 was made by 

 galvanizing the sciatic nerve at -|-, after section of the par vagum and division of the nudulia 

 at its junction with the i)ons ; the dog being curarized and artificial respiration practised. The 

 break in the tracing wu.s pmdnceil by the rise of the needle of the manometer above the drum : 

 at -f--f the current was broken. Fig '2 represents the effect of applying a galvanic currint in 

 the same strength and method as Ix-fore to the same dog, after he had suffereil further mutila- 

 tion by section of the s]ilaiH'hnies ; -\- indicates beginning, -\--\- end of irritation. 



Fig. 3. Tracing of E.xperiment 100, p. 151. This tracing shows the effect of a feeble current upon 



bliHMl pressure when applied to the Ilitzig brain regions; curarization and artificial re8)iirution 

 iH'ing practised. The current was applied anil intfrru|ited at points niurked ; one needle or 

 pole ticing in each region Tin' traring was made with a very inferior curdionieter. 



