86 PHYSIOLOGY OF STREAMING MOVEMENTS 



progressively increases until an almost immediate stoppage of streaming 

 and coagulation of the protoplasm ensues. Theoretically there should 

 be a percentage of alcohol which leaves streaming unaffected, but as a 

 matter of fact, even when gradually applied, a strength of solution which 

 causes at first an acceleration (2 to 5 per cent) may ultimately produce 

 a retardation, while a solution strong enough to cause no acceleration 

 produces a progressive retardation. 



The retarding influence of strong alcohol is easy to understand, being 

 mainly the result of the withdrawal of water, but the accelerating influence 

 of dilute solutions appears to be due to a direct chemical action on 

 the protoplasm. Dilute glycerine also directly accelerates streaming, 

 strong glycerine retarding or stopping it An indirect stimulating effect 

 may be exercised in some cases, as when treatment with strong glycerine 

 and subsequent washing in water cause streaming to appear in previously 

 quiescent cells. 



Both alcohol and glycerine rapidly penetrate the protoplasm, but 

 since alcohol has nearly the same viscosity as water 1 , while that of glycerine 

 is very much greater, the acceleration of streaming can hardly be due 

 to any direct change of viscosity produced by their mere presence. An 

 indirect effect upon the viscosity of the protoplasm is quite possible, 

 although more probably both of these substances exercise some chemical 

 effect, causing either a general increase of katabolism, or a greater 

 liberation of the kinetic energy utilized in streaming. Alcohol and 

 glycerine both exercise a pronounced influence upon animal metabolism, 

 the former accelerating katabolism, while the latter increases the production 

 of glycogen by the liver. 



SECTION 37. Anaesthetics. 



Kuhne- was probably the first to show that chloroform and ether arrest 

 streaming. Very dilute solutions of ether at first slightly accelerate 

 streaming, and it is interesting to notice that the inhalation of ether acts 

 at first as a nervous excitant upon animal organisms. Solutions in water 

 of from 10 to 25 per cent, saturation of both chloroform and ether at 

 once retard streaming, and ultimately cause it to cease without any 

 temporary quickening preceding death, as often occurs in other cases. 

 If, however, the action is not unduly prolonged, on returning to water 

 the streaming may become for a time more active than it was before, 

 whereas a continuance of the previous retardation usually indicates that 

 the cell has been fatally affected. Hauptfleisch (1. c., p. 220) has shown 



1 When alcohol is added to water, the viscosity increases. 



* Unters. iiber das Protoplasma, 1864; cf. also Klemm, 1. c., p. 54, Repr. ; Overton, Studien 

 uber die Narkose, 1899. 



