April 7, 1916] 



SCIENCE 



507 



group of constituents by the aggregation eSect 

 of another, the solution equilibrium of the 

 surface colloids of a cell exposed to such a 

 combination would remain unchanged. Stated 



ooeg. pt/' 



That there is some physical-chemical prin- 

 ciple behind all " antagonisms " is strongly 

 suggested (1) by the appearance of the compen- 

 sation phenomenon between such widely unre- 



teraperature 



A. 



Fig. 1, A. An empirical curve representing the 

 liquefying action of atropine upon the melano- 

 phores of Fundulus at different temperatures. The 

 points are relative. Thus at 22° C. there is more 

 liquefaction than at 10° C, but less than at 36° C. 

 At 37° C. there is again less liquefaction than at 

 22° C, but more than at 5° C. Up to 36° C. the 

 temperature ooefScient of liquefaction is therefore 

 positive, while beyond 36° C. for a few degrees, it 

 becomes negative. 



in physiological terms, if we could compen- 

 sate coagulative and liquefactive forces at the 

 cell surface, the vital equilibrium would re- 

 main normal and we should obtain no injuri- 

 ous effect. Compensating effects of this sort 

 are actually realized in solutions like those of 

 Ringer and Locke, or in sea water. We have 

 here a number of combined chemical stimuli 

 which, when acting singly, produce distinct 

 liquefactive or coagulative effects upon living 

 cells, but which, in combination, are relatively 

 harmless. According to the conception of a 

 solution equilibrium at the cell surface, the 

 non-injurious effects of compensated solutions 

 of two or more constituents are to be referred 

 to the failure of these solutions markedly to 

 increase or decrease the solubility of the col- 

 loidal disperse phases. Such phenomena of 

 physiological compensation have been cpUec- 

 tively termed " antagonisms." 



B. 



Fig. 1, B. Ostwald's curve showing the effect 

 of elevated temperature upon the viscosity of egg- 

 white. Here the temperature coefficient of lique- 

 faction is positive up to about 57.5° C, while be- 

 yond this point to about 60° C. it becomes nega- 

 tive. 



A comparison of the two curves shows that 

 above and below a critical point in each system 

 (36° C. and 57.5° G.) the temperature effects are 

 antithetical. 



lated chemical sub.stances^^ and (3) by the 

 compensation that appears between liquefying 

 agents and elevated temperature. This last 

 case seems of such importance as to warrant a 

 detailed consideration. 



If a colloidal solution of egg-white be gradu- 

 ally heated to 35°-40° 0. it becomes slightly 

 less translucent, i. e., there is an increased 

 dispersion. A viscosity measuremenf^^ shows 

 that an increase in fluidity continues uni- 

 formly up to about 57.5° C. At this point 

 there is a sharp reversal of the reaction and 

 the viscosity rises rapidly to about 60.0° C, 



^^For example "antagonisms" have appeared 

 between various alkaloids sozch as atropine and 

 eserine, nicotine and curare, between alkaloids and 

 salts as atropine and CaCL and MgClj and be- 

 tween such salts as KCl and cobalt hexamine 

 chloride (Hober u. Spaeth, loc. cit.). 



13 Ostwald, Wo., '13, Koll. Zeitschr., 12, 213. 



