274 Dr. X. H. Alcock. On the Negative Variation [Jan. 17, 



work equally well with all classes of nerve, and carefully preserving' 

 similar conditions of experiment, the results in the different series 

 are strictly comparable not only with each other, but also with Halli- 

 burton's* researches on the heat-coagulation of the nerve proteids. 

 The excitation was a maximal one throughout. 



Series I. 



A. With Laboratory Frogs. 



B. With freshly-caught vigorous Frogs. 

 Sciatic nerve. Excitation 30, except in A e . 



Experi- 

 ment 

 No. 



Hours 

 post- 

 mortem. 



Temp, 

 of nerve 

 cham- 

 ber. 



Temp, 

 of hot 

 bath. 



Neg.var. 

 initial 

 = a. 

 0001 v. 



Neg. Tar. 

 final 

 = 6. 



T • 1 



Irrita- 

 bility 

 quotient 

 _ b 

 a 



Notes. 





h. m. 















A c 



1 



room 



43° -5 



10 











1 



A* 



2 7 





40-7 



0-8 











A ha 



5 



if 



40-0 



1 -2 











1 



A hb 



5 30 



5) 



39*0 



] -8 



0-56 



0'31 



Ae 



2 30 



J J 



38 '5 



1 -7 



1 7 



1 -o 



J 



A* 

 A* 

 Ay 

 A v 



6 



2 40 



3 30 

 2 



17° C. 

 15° C. 



42-1 

 42 

 41 1 

 40 -0 



25 

 2 3 

 1 -8 

 - '7 





 



91 

 3'0 





 



0'51 

 1-7 



1 



r 



Series II. 



Babbit. Sciatic. Excitation 1000 for first three experiments, 

 last four, 500. 



Experi- 

 ment 

 No. 



Hours 



post- 

 mortem. 



- 



Temp, 

 of nerve 

 cli am- 

 ber. 



Temp, 

 of hot 

 bath. 



Neg. var. 

 initial 

 = a. 

 -001 v. 



Neg. var. 

 final 

 = b. 



Irrita- 

 bility 

 quotient 

 _ b 

 a ' 



Notes. 





h. m. 















flfa 



f> 30 



33°0 



48°5 



0-53 



0-12? 



0-22? 



Doubtful re- 



B ca 



3 30 



29 -0 



48 -0 



0-57 











turn. 



B d 



5 30 



30 -0 



47-7 



0-83 



25 



0-30 





A u 



4 



20-5 



46 -0 



11 



0-45 



0'41 







6 35 



21 



44'3 



0-52 



0-34 



0-65 





A m 



5 



19 -0 



42 -3 



0-48 



52 



11 





A* 



2 45 



19 -0 



39 '5 



0-76 



0-69 



0-91 





* Halliburton. " Croonian Lecture," 1891, and below. 



