528 



PROCEEDINGS OF THE AMERICAN ACADEMY. 



Spark. Calcium chloride on carbon electrodes. 

 Arc. Calcium chloride on carbon electrodes. 

 Wehnelt. Platinum point in calcium chloride solution. 



Strontium. 



The spectrum is in general similar to that of the spark, the order of 

 intensities agreeing well in the majority of instances. A few of the 

 stronger spark lines, with intensities sufficient to make them visible if 

 they were present in normal intensity, are not to be seen. Among these 

 the group X 5225-X 5257. The "oxide" bands are bright. 



The same question arises here as in the case of calcium. In the 



