58 ii:vi:k. 



KXIKUIMKNT 48. 

 A lerriur bitch of ra«>'!' --ki.' -'</<■ mul >trciij:ili. 



Tim H»CT. Tutf. li^;MAHK^S 



II:4:<A. M. 



ll:-»7 103 .2j F. Cut the nicdullu. Hrouthiog ul oncu ccum-U itlmcMt entirely, bo tli&t the dog wu tt 



mil' time tliuii);lit tu be Ji-ud, uiid urtiBcial rvspiratioii, by cuni|ircMi(ig the hody 

 with the hand, wus rcsurted to. 



{1-^3 Dog beginning to breiithc voluntarily, conjunctiva uot wiuiilivc, complete par»ly»ii 



of bi-nsutlun and motion throughout the body. 

 11:54 103.S0 Temp, of room 7lP. 



M:«0 103.75 



12:l5r.il. 1(13.75 I'"" '•l><i»^ im nthrr »i).'ii.K uf lifi' tliiin thr xlcw. n'L'iilur breathing. 



12:30 1(>3.75 



r.':10 104. 



rj;j5 104 25 Hreothing noiny, irregular. 



12i5 104. 7'i Ucneral niu.sonlar ri(.'iilily, with frequent convuUionii and Iri'mnr; Imlh nymptomt 



arc much aggravated by any irritation of the eurfoce. Legs htiOly extended, 

 tail forcibly drawn down between them. 

 1:15 li.ii. Temp, of room 70-'. 



2:10 107.75 Thermometer is now in abdominal cavity (has t>ecn in the rectum). The dog bu 



been vomiting freely. 



2:15 Arterial pressure l.'iO-ICO; galvanization of a nerve caused it to fall to I20-12.V 



2:20 108.135 Cut the par vagum. Hrcathing at once almoKt suspended. 



2iJ2 Respiration only at very long intervals. Ulood in arteries venous. On ronnerting 



a rardiometer tube with the femoral, the mercury rose to the top of the tube 

 (20.')) and flowed over in abundance. 

 2:25 There has been no breathing for sonic minutes. Heart has not ceased to beat. 



Auliipfij. — Kiiifo hu.s pas.sed tliroagh the cerebclluiu, scraping the posterior surface of upper por- 

 tion of inedalla, aud cutting it very obliquely at its junction with the poos. 



In looking over the records of these experiments, it will l)e found that tlioy 

 npiM-ar very conclusive, in regard to the rise of teniperatnre which follows division 

 of the mcdnlla high up. One of the most powerful means of lowering the tempcrn- 

 turc at our rnniiuand is venesection, and yet. although the dog in Kxiiciinunt 4() was 

 almost hied to death, tiie temperature rose from the time the medulla was divided. 

 In Experiment 47 the animal temperature was extraordinarily high, and yet the 

 temperature began to rise at once after the operation. In Experiment 48 no bleed- 

 ing of any moment occurred, and the elevation of temperature was therefore more 

 niarkfd than in the first trial. The rise commenced immediately after the division 

 of tlie medidla, and amounted to almost five degrees, and was still increasing when 

 the animal died. As the temperature of the surrounding air in both cases was not 

 over seventy, the evidence is conclusive. 



In neither case were the vaso-motor centres paralyzed. In the first experiment, 

 after division of the par vagum, galvanization of a sejisitive nerve was followed by 

 a slight but tlistinct rise of the arterial presstire. The reason that this rise was so 

 slight was probably the very small amount of Idood in the vessels const-qnent upon 

 the hemorrhage, so that contraction of the arteries was not followed by its usual 

 effects. 



In the smaller dog, the evidence that the general vaso-iuotor system was intact, 

 was tinimpcaehable. .\t first, the galvanization of a s«'nsitive nerve rediu-ed the 

 pressure, very decidedly, on account of its infiuence on the par vagum and the luart. 



