Jaxvaey 22, 1897.] 



SCIENCE. 



137 



contact with the nerve-endings replacing 

 fatigue of these themselves. 



The ' discharge hypothesis ' affords a new 

 conception of the real nature of inhibition 

 and accounts for the actual properties of 

 inhibited muscle. The anelectrotonus of 

 the muscle substance, which must neces- 

 sarily accompany the more active kate- 

 lectrotonus even in the case of the action 

 current of the motor nerve-ending, may not 

 iuconceivablj'^ become by greater anodic 

 current density the more active in the case 

 of the action current of inhibitory nerve- 

 endings, and be the essential factor in the 

 production of inhibition. 



Gum arable and the frog's heart. F. S. 



Locke. 



The author has again found, in contra- 

 diction to M. Albanese's recent statement, 

 that sodium arabate, unlike gum arable 

 (from which it differs by containing sodium 

 in place of calcium, magnesium and potas- 

 sium), confers no special sustaining power 

 on 6 per cent, sodium chloride solution, 

 weakly alkalinized with sodium carbonate 

 and saturated with oxygen. 



The measurement of the output of the heart. G. 



N. Stewart. 



A solution of a substance (e. g., sodium 

 chloride), which can be easily recognized 

 and quantitatively estimated in the blood, 

 is allowed to flow at a known rate for a 

 measured time through the external jugu- 

 lar vein into the heart. When the mixture 

 of blood and injection liquid has reached a 

 convenient point of the arterial system be- 

 yond the heart, e. g., the femoral artery, a 

 sample is drawn off during its passage. 

 From the composition of this sample, the 

 amount of blood with which the injection 

 liquid must have been mixed in the heart, 

 that is, the outflow (or inflow) of the heart 

 during the time of injection, is determined. 

 The electrical resistance of the mixed fluid 

 being different from that of the blood, a 



telephone is employed to announce the 

 time of arrival at the point of observation. 

 So far the results seem to show that the 

 more recent measurements of Tigerstedt, 

 Stolnikow, etc., are too low, while those of 

 the older observers (Volkmann, etc.) are 

 too high. 



As a preliminary to this investigation the 

 author shows that when the time of injec- 

 tion is not too short it is approximately 

 equal to the time of passage of the altered 

 blood through a given cross-section of the 

 carotid or femoral artery. The circulation 

 time of the lungs, as determined by the in- 

 jection of methylene blue in rabbits and of 

 NaCl by the telephone method in dogs, is 

 approximately the mean pulmonary circu- 

 lation time and not the minimum. This is 

 also the case for such artificial schemes as 

 approach the condition of a vascular capil- 

 lary tract. 



Demonstrations of apparatus. G. W. Fitz. 



1. A spring cylinder chronograph for 

 spark records. 



2. A lever system to illustrate the action 

 of muscles in relation to joints. 



3. A form of student's myograph. 



4. A modification of the location reaction 

 apparatus. 



Demonstration of preparations of the nerve cell 

 under acute alcoholic poisoning. C. F. 

 Hodge (for C. C. Stewart). 

 Specimens to illustrate Mr. Stewart's re- 

 cent paper (Journal of Experimental Medi- 

 cine, Vol. I., 'No. 4l, 1896) were demon- 

 strated to the Society. In the experiment 

 cats were used, one being held in alcoholic 

 stupor for 54|^ hours, a second 50 minutes, 

 death being caused by alcoholic poisoning 

 in both cases, and a third being killed by 

 decapitation. From the three animals, 

 thus dead at the same time, corresponding 

 portions of the nervous systems were re- 

 moved and immediately placed in the same 

 dishes of the several fixing and hardening 



