356 PRINCIPAL HENRY A. MIERS AND MISS FLORENCE ISAAC ON THE 



Experi- 

 ment. 



32 



33 



Concen- 

 tration. 



per cent. 



95 



92-2 



Remarks. 



The goniometer trough was heated to 30 before putting in the solution. The index 

 rose from 1-432300 at 50 to 1 -437123 at 38. A shower of /8-crystals occurred 

 very suddenly at 38, the temperature rising to 42 -5 and the index falling to 

 1 434354, when the solution became opaque. 



The trough was again heated to 30 before putting in the solution. The index rose 

 from 1 430077 at 46 5 to 1 436265 at 32. At 32 a dense shower of /^-crystals 

 occurred very suddenly, the temperature rose to 35 5, and the index fell to 

 1-433491. The temperature then fell again, but the density of the shower 

 prevented any further readings. On inoculating the solution with a, transforma- 

 tion from /3 to a took place, and the temperature rose again from 35 to 39 5. 



The index-temperature curves of these two experiments, at the temperatures at 

 which they attain their highest refractive index, give points which lie very 

 approximately on the supersolubility curve of fig. 6 as previously determined. We 

 may assume, therefore, that in experiments 20, 21, 22, and 23 the stirring was not 

 sufficient to bring down the /3-showers on the supersolubility curve, and that the 

 solutions therefore passed somewhat into the labile region. 



III. Solutions first giving y-shoivers. 

 (In all these experiments the larger goniometer of fig. 4 was used.) 



