( 726 ) 



Bottomley ') showed thai the lateral flow of water causes a great 

 retardation. 



The experiments now showed (hat (his lateral flow really exists. 

 For even when the ice was perfectly clear, in the places where the 

 wire had passed through it various small bubbles were observed. 

 Consequently not all the ice had been re-formed which had been there. 



In this respect I also mention a curious change, found in the 

 values of C: these values rise with the weight. This is very con- 

 spicuous with the silver and german silver wires, but also with the 

 steel wires it exists, especially with the thick one of 0.87 mm. 



Accordingly it was often seen that the bubbles on the path of 

 the wire were more numerous with small than with heavy weights. 

 This became particularly clear in experiments in which, during one 

 descent, first a heavy and then a small weight was used, With the 

 smaller weight more water flows off laterally. 



I still made several experiments in which the wire was pulled 

 upwards through the ice, hoping to prevent this lateral flow. The 

 result was not the expected one, for bubbles also appeared and the 

 values, found for 6', were even somewhat smaller than in the former 

 case. In regard to this question it would be desirable to investigate 

 the descent of a whole body, e.g. of an iron ball, through perfectly 

 clear ice. 



In my opinion this lateral flow is the chief reason why theory 

 and observation disagree. It also explains why with the silver wires 

 larger differences were found than with the german silver and the 

 steel wires. For if the heat is only partly furnished by the freezing 

 process above the wire and if the rest has to be furnished by con- 

 duction through the ice, it seems to be of little consequence whether 

 the wire be a good conductor of heat. 



5. Ice is a crystalline substance. This also may have its effect. 

 Perhaps the melting point is not the same at the different faces of 

 the crystals which the wire touches. Though this influence may exist, 

 we cannot say in which direction it would modify the result. 



In order to find out whether such an influence makes itself felt, 

 I made the wire pass several times through the same block of ice 

 in three mutually perpendicular directions. But no perceptible diffe- 

 rence was found. 



As the general result of' the experiments I think we may state, 

 that they indicate that the regelation theory will be found capable 

 of explaining the phenomena not only qualitatively but also quanti- 

 tatively . 



x ) Pogg. Ann. 148, p. 492, 1871. 



