gaseous phase would bo attained because the copper compounds 

 themselves have a catalytic action at the temperatures liere employed'). 

 Table VI where the P' series has been executed without, and the 

 2nd ,vith addition of platinum confirms this entirely. 



12. The gas mi.\ture was withdrawn a few times by suction until 

 a fall took place in the equilibrium pressure; the reaction product 

 was then analysed and gave the proportion 2CuO : SO, = J : 0.98. 

 This product gave afteiwards tiie pressures of table VII, these 

 always returned after continued evacuation, until finally the pressure 

 fell to that of the equilibrium 4CuO ;± 2Cu,0 + 0,. Further basic 

 sulphates are, therefore, not capable of existence at these temperatures. 



T A B L E VI. 2 CUSO4 7^ CuOCuSOj + SO3 [SO. + 1/2 O.,] (fig. 3, line VI). 



TABLE VII. CuOCuS04~t2CuO + S03[SO.-fi,oO„] (fig. 3, line VII). 



1) BoDENSTEiN and Fink. Zeilsclir. f. physik. Gliem. 60, 46 (1907). 



L. WöHLER, W. Plüddemann and P. Wohler, Zeitsclir. f. phys. Cliem. 62, 641 (1908j. 



