384 MR. P. 0. PEDERSEN ON THE SURFACE-TENSION OF LIQUIDS 



GRUNMACH'S results. I cannot, however, omit to draw attention to the fact that the 

 mutual agreement between GRUNMACH'S values is only small. Within the first group 

 of measurements the deviation amounts up to 16 per cent., and for the last to 3 '9 

 per cent. 



The lowest of GRUNMAOH'S values in the two cases are 



T 15 = 70'4 dyne/cm, and T^ = 74 '2 dyne/cm. 

 Both are lower than the values found here. 



Toluol. 

 The value found according to Table XVI. is 



TIJ = 2876 dyne/cm., 



in complete agreement with VOLKMANN'S results, namely, 



TIS = 2879 dyne/cm. 



This was to be expected, as in this case the initial and the stationary value of the 

 surface-tension must be very nearly equal. 



Aniline. 



The liquid used was marked " pure," but was, however, a little coloured. 

 The result of the measurements is shown in Table XVI. The value is 



T 15 = 43-00 dyne/cm. 

 The corresponding value by VOLKMANN is 



T,, = 44-30 dyne/cm., 



also considerably larger. To this may be remarked that VOLKMANN himself estimates 

 his determination as somewhat uncertain, and, further, that aniline is somewhat 

 soluble in water, so that there has possibly been formed a layer of water on its 

 surface. Using the method of the maximum pressure of small air bubbles, FEUSTEL* 



found - : T I = 46-6 dyne/cm. V ^ \ f/ ' 



Aqueous Solutions of Ammonia. 



Measurements were -made on three solutions of ammonia. The values are (see 

 Table XVI.), 



For /3 151 = 0-99030, T 16 = 71 '25 dyne/cm., 



/is,4 = 0-97921, T, 8 = 68-02 dyne/cm., 

 = 0-95801, T 16 = 64-69 dyne/cm. 

 * FEUSTEL, loc. tit. 



