Properties of Aqueous Mixtures and Solutions. 



161 



Percentage 



of alcohol, by 



weight. 



Volume at 

 io°C. 



Volume at 20 C, 

 found. 



Volume at 20 C, 

 calculated. 



Difference. 



o 



100 



100*154 



100*154 







IO 



100 



100*212 



100-272 



— *o6o 



20 



100 



100*405 



100 386 



+•019 



3° 



100 



100*632 



100-498 



+ -I 34 



40 



100 



100783 



100*601 



+ •182 



45 



100 



100-827 



100-652 



+ •175 



5° 



100 



100-868 



100*700 



4-*i68 



5977 



100 



100-914 



100*789 



4-*i25 



6973 



100 



100-980 



100*874 



4-*io6 



7981 



100 



I0I - 020 



100-954 



+ •066 



89-89 



100 



IOI'052 



101*034 



+•018 



IOO'OO 



100 



IOI*o88 



101*088 





Percentage 



Compressibility 



Compressibility for 





of alcohol, by 



for one 



one atmosphere, 



Difference. 



weight. 



atmosphere, found. 



calculated. 









0*00004774 



0*00004774 





10 



0*00004351 



0*00005387 



0*00001036 



20 



0-00003911 



0*00005998 



0*00002087 



3° 



0*00003902 



0*00006584 



0*00002682 



40 



0*00004347 



0*00007118 



0*00002771 



45 



0*00004608 



0*00007366 



0*00002758 



5o 



0*00004878 



0*00007600 



0*00002722 



5977 



0*00005620 



0*00008029 



0*00002409 



6 973 



0*00006159 



0*00008426 



0*00002267 



78*81 



0*00006942 



0*00008775 



0*00001833 



89*89 



0*00007950 



0*00009140 



o*ooooi 190 



IOO'OO 



0-00009349 



0*00009349 





"Weight of water contained in the piezometer 114*9/27 grms. 



In conclusion the authors confine themselves to pointing out cer- 

 tain relations which connect the various physical properties examined. 



These properties may be divided into two classes, according as 

 they reach a maximum deviation from the theoretical mean at 30 

 per cent, or 40 per cent. ; each of these is divided into two sub- 

 classes, one containing those properties in which the numbers found 

 are above those calculated, and the other containing those in which 

 they are below. 



Class I. 



Subclass a. Specific heat. 



Heat produced by mixing. 

 ,, b. Boiling-point. 



Capillary attraction. 

 Class II. 



Subclass c. Rate of expansion. 

 ,, d. Compressibility. 

 Other characters, examined by previous investigators, are : — 



1. Vapour-tension : this falls under Class I. Subclass b. 



2. Specific Gravity. 



3. Index of refraction* 



Phil. Mag. S.4. Vol. 38. No. 253. Aug. 1869. M 



