196 THE EAEL OF BERKELEY, MR. E. G. J. HARTLEY AND DR. C. V. BURTON: 



Date. 



March 19 



Remarks. 



Rammed down ice. 



Rammed down ice. 

 Rammed down ice. 

 Rammed down ice. 

 Rammed down ice. 

 Rammed down ice. 



The weight concentration of the solution before filling the compressibility tube was 38-812 gr. of 

 anhydrous salt to 100 gr. of Aq and its density 1 2432 at C. 50 c.cm. of this solution were pipetted into 

 the bulb and, during filling, gave up to the H 2 SO 4 U-tubc a weight of 0-028 gr. of water, from which it is 

 deduced that the concentration of the solution filling the compressibility tube was 38-834 gr. 



Reduction of Observations of Compressibilities. 



(1) Determination of Compression of Compressibility Tube. The observed change 

 in volume of the liquid filling the compressibility tube is the algebraic sum of two 

 terms the actual change of the liquid less that due to the glass itself. 



As stated, the compressibility tube was made of Jena glass 16 111 and the compressi- 

 bility of this glass has been worked out by STRAUBEL* and others (see LANDOLT and 

 BORNSTEIN'S tables, 3rded., for references) to be '00000228 per atmosphere at ordinary 

 laboratory temperature. 



There seems to be good reason for believing that AMAGAT'S value for the compression 

 of mercury is accurate (see JAMIN, ' Cours de Physique '), so that by using this value 

 and observing the apparent change in volume of the compressibility tube when rilled 

 with mercury a check on the above coefficient of the glass can be obtained. 



An experiment in which the compressibility tube was exhausted by means of a 

 Gaede pump and then filled by recently redistilled mercury gave 4 0169 as its 

 apparent coefficient of compression in the compressibility tube between 1 and 101 



* The value in LANDOLT and BORNSTEIN'S tables seems to have been derived from torsion and bending 

 experiments. 



