

Atilofonj. — Rijrlit luul li-ft side uf ilif liriiiii jlcsiroyoil to the ventricles over n liirpc t^iirfuce inrolT- 

 iiiir iIh' ru'-.t M'lMiiiI. uikI lliinl i-iiiiVMJutioli.''. uiul rrucliiii^' to the sulrii-^ rriirialii.- in fnitit. 



In tlio first of these experiments (Experiment 104) the verj' powerful current 

 (the full force of the apparatus) applied in the bef^inning to the llilzig's region, 

 produced general tetanus with rise of the blood i)ressure. This was at ll:'2(l a.m. 

 More curari having been given, suflieient to entirely paralyze vohnitary niovt inent, 

 n mild curn'iit, hut one suflieient to he very jtaiuful tt» the tongue, was applied to 

 the brain at ll:'i.3:;}() a. m. Tliis failed to produce rise of ])n*ssure, as is shown 

 ill the tracing Plate II. Fig. 4. This current was certainly sufficiently powerful 

 to have violently affected the blood jnessure, if it had been api)licd to a sensitive 

 nerve. At ll:'J(i A. M. the current was increased to tlie full power of the coil, with 

 the sudden rise of pressure, that is depicted in the tracing. Later on in the 

 experiment, the nozzle of a syringe was forced into the brain, and a stream of 

 water driven forcibly in. At once the blood ])ressurc rose from 'iOO-'i'JO up to 

 ;j.>()-4(H), and maintained itself at 2H()-'2i)0 for four minutes, till the lower brain 

 was broken up with a pithing instrument. 



In the next experiment (Experiment 105) a very decided current, sent through 

 the brain before section of the vagi, caused an immediate rise of pressure, which 

 may have been due to the general muscular tetanic tremblings. After the vagi 

 were cut, the pressure stood at 'i;?0-i;J5. AVhen an instrument was jdunged 

 into one of the llitzig's regions and the brain destroyed, the mercury at once rose 

 to '250-2()0, and the brain being still worked with, the pressure was maintained 

 for some seconds at 2"l)-2S(); on ceasing the operation the mercury fell to 2:J0. 

 ^^ ater was now forced into the brain, bringing away large masses of it ; the merctiry 

 immediately rose to 2()0 aud 270, and although only ten or fifteen seconds were 

 occupied with the process the pressure maintained itself at 2o0-2o5 for more 

 than a mintite, when the experiment was hrotight to an end. 



The last cxperiuient of the series (Experiment 10(5) is in accord with the others; 

 a mild, but d<-cided. fararlic current applied to the llitzig's region had no decided 

 eff"eet upon the blood pressure. This was tried three times; at 1:10:")0, at 

 1:1:J::}0, and at 1:2^:30. At the first ap]dication there was apparently in the Ixv 

 ginning a rise of pressure; but as this did not continue in this case, and did not 

 occur at all in the other instances, it was probably due to some accidental extrano- 

 r)us momentary cause. A powerful current was applied to the brain at l:2*.):3fl, 

 nnrl prcMluccd a slight rise, wliieh may have been due to the violent struggles; this 

 is seen in the tracing Plate II. Fig. 6. The lack of the effect in the final 

 trial is well shown in the tracing Plate V. Fig. 3. Destruction of tlie llitzig's 

 region ilid not have us nuu ii effect as in the preceding experiment, but produced 



