S. Taker — Growth of Crystals. 



547 



glass tube having an interior diameter of 7 millimeters. The 

 walls of the chamber were about 0'3 millimeter thick. The 

 apparatus was set up as shown in figure 4. A saturated 

 solution of copper sulphate at room temperature (about 20° C.) 



Fig. 4. 



Saturated Copper Sulphate Solution 



Water 



Inches 



Fig. 4. Apparatus for growing crystals under pressure, with glass crys- 

 tallizing chamber ready to be ruptured by growing crystals. 



was drawn from a large reservoir by means of a glass siphon 

 and passed through the crystallizing chamber, the rate of flow 

 being controlled by a pinchcock placed near the end of the 

 outflow tube. The surface of the solution in the reservoir 

 stood at an average elevation of about 50 centimeters 

 above the crystallizing chamber. The latter was kept at a 



