Determination of the Surface Tensions of Liquids, 121 



A glance at the tables shows that the " constants " are 

 indeed quite constant. In Table I, the average of the num- 

 bers in the last column is 1*24:3 ; the greatest variation on one 

 side is 0*019 for carbon bi-sulphide at 9° -7, and on the other 

 side, 0*016 for toluene at 4:Q°'Q. Generally, the differences 

 from one liquid to another are not larger than they are for the 

 same liquid from one temperature to another. Likev^ise, in 

 Table II, the average value of the constant is 1*022, with dif- 

 ferences of 0*014 for ether at 20°*0 on the one hand, and 0*011 

 for chlorbenzene on the other. 



Introducing c=l*243 from Table 1 and c= 1*022 from 

 Table II into equation (A), and treating y as the unknown 

 quantity, I calculated the capillary constants to be those given 

 in Tables III and lY, respectively, beside which are placed 

 the corresponding data by Ramsay and Shields (loc. cit.) and 

 Ramsay and Aston (loc. cit.) 



TABLE III. 

 Comparison of Capillary Constants for Tubes A and B, 



c=l-243. 



Names of Liquids. T 



Water 30°*0 



Methyl Alcohol 20°*0 



Ethyl " 20°*0 



Acetone 16°*8 



" 46°*4 



Ethyl Ether 20°*0 



*' " 30°*0 



Ethyl Iodide lO**! 



Carbon Bisulphide. 9°*'7 



Benzene -_. 11°*2 



46°*0 



Chlorbenzene 9°'5 



'' 45°*6 



Toluene 15° -2 



" 46°-6 



7 

 y=chs + i 



68-82 



67-42 



23*39 



22-lT 



23*34 



19*59 



16'42 



15-18 



29*90 



33*22 



29*31 



24-75 



33*86 



29*68 



27*96 



24*25 



Eamsay and Shields. 



69 

 67 

 23 

 22 

 23 

 19 

 16 

 15 

 30 

 32 

 29 

 24 

 33 

 29 

 28 

 24 



*10 

 *50 

 ■03 

 •03 

 •35 

 •68 

 -49 

 •27 

 -00 

 *73 

 •21 

 •71 

 *71 

 *30 

 *18 

 •60 



7—7' 



— 0*28 



— 0*08 

 + 0*36 

 + 0*14 



— 0*01 



— 0*09 



— 0*07 

 -0*09 



— 0*10 



— 0*49 

 + 0-10 

 + 0*04 

 + 0-15 

 + 0-38 



— 0-22 



— 0*35 



TABLE ly. 

 Comparison of Capillary Constants for Tubes B and C. c=r022. 



Names of Liquids. T 



Acetone 16°*8 



" 46°*4 



Chlorbenzene 45°*6 



77°*8 



Ethyl Ether 20°*0 



Benzene . _ 1 1 °-2 



.-- _ 46°^0 



(( 



Toluene 15°^2 



" 46°*6 



" 78^**4 



7 

 zchs + s'^ 



23-32 



19-64 



29-56 



2601 



16-42 



29-28 



24-88 



27-93 



24*46 



21-09 



and Shields. 

 23-35 

 19-68 

 29-30 

 25-66 

 16-49 

 29-21 

 24-71 

 28*18 

 24*60 

 20*93 



y—7' 



— 0-03 



— 0-04 

 + 0-26 

 4-0-35 

 -0*07 

 + 0-07 

 + 0*11 



— 0*25 



— 0*14 

 + 0*16 



