100 Hartiry—An Investigation of the Connexion between 
There is a similarity between this spectrum and those obtained by means of 
the Mecke burners, with and without the air-blast. 
The greatest difference occurs with the solution containing 0°001 per cent. 
of calcium, as in this case the bands have been reduced to lines. 
Spectrum with a Condensed Spark taken from Metalic Calcium. 
Eder and Valenta examined and published an account of the spark-spectrum 
of calcium, and by reference to this the lines have been identified. (K. Akad. 
Wissenscht. Wien. '7'7, 1898). 
The wave-lengths of the lines have been adopted from their memoir. 
Wratten and Wainwright’s panchromatic plates were used. ‘Thirty-four lines 
were counted between A 6499°9 and d 5624. 
STRONTIUM. 
Oxyhydrogen Flame Spectrum. 
Strontium nitrate was dissolved in alcohol in such proportion that 0:00876 er. 
of strontium was contained in 1 ¢.c. of the solution. Photographed with Wratten 
and Wainwright’s panchromatic plates. 
Weight of Description of Spectrum photographed. 
Strontium. 
0:0175 gr. Lines visible AA 6086, 6058, 4607. 
0:0087 gr. Only one line visible \ 4607. 
0:0043 gr. Only one line visible \ 4607. 
0:0035 gr. Nothing visible. 
Strontium—Spark without Condenser. 
These spectra were not photographed, but observed by the eye, the sparks 
being taken from solutions in a fulgurator. 
