133 



have a greater molecular weight than those thai are not Iraiisformed 

 or hardly so; again, the former generally bring about a more con- 

 siderable lowering of the surface-tension of water. For the solutions 

 examined upon their Tyndall effect the number of droplets decreased 

 in an orderly manner. Calling the number of droplets for pure water 49, 

 that of eiigenol is 90, crissol 80, carvacrol 80, citral 72, thymol 72, 

 guaiacol 70, cumidin 65, hypnone 54. This series corresponds 

 approximately with the one holding for Tyndall's effect. On the whole 

 there is an orderly decrease in the power to |)roduce a lowering of 

 the surface tension between air and watei-, similar to that of the 

 power to bring about a colloidal condition of the saturated or half- 

 saturated solution. 



When examining our solutions ultramicroscopically while standing 

 for days and weeks, at various intervals, the number of submicrons 

 appears to augment^) to the detriment of the amicrons, which formed 

 the base of the cone. In strong colloid solutions there ultimately 

 appears a precipitate, as in the case of ciigenol. By the addition 

 of. 7i '1- sodium-carbonate solutions the markedly opalescent fluid at 

 once becomes rather more translucent, in which process amicrons 

 re-appear, this time to the detriment of the spontaneous submicrons 

 previously formed. 



Prior to and subsequent to tiansformation the surface-tension of 

 the solution is appi'oximately equal (with a eugenol solution 1 : 1500 

 fresh 67 and old 67 droplets for the stalagmometer volume). Also 

 the smell-intensity is the same before and after transformation. Upon 

 this basis we feel justified in terming the transformed odorous solutions 

 "suspensoids". Exposed in the usual way in an U-tube to the action 

 of a constant electric current, the particles in these siispensoids were 

 all moved towards the anode. It follows then that the particles 

 themselves must be negatively charged. The ai-m with the -}- pole 

 was getting more opalescent, the one with the — pole cleared up. 



After reversal of the current the previous state w^as restored. 

 Likwise the previous intensity of Tyndall's effect is restored by mixing 

 the contents of the two arms. The following table gives the quantitative 

 relations of the light-intensities of the Tyndall effect of the solutions, 



1) The fluids, the colioicUil as well as the fresh-prepared control fluids, were 

 instantly filtered in the cuvette through a paper filter. Consequently with pure 

 water only half a dozen submicrons at the most were discernible in a microscopic 

 field. With water a base of amicrons was altogellier lacking, similarly with the 

 fresh control-fluids; but in the saturated or partly saturated solutions that through 

 standing had been changed into suspensions, we discerned besides a base of 

 amicrons a very large number of submicrons in active Brownian movement. 



