Beryllium and the Vreeland carbon arc visual spectroscope.
The spectrum of beryllium was especially challenging to obtain, prompting the use of an forty year old instrument, the Vreeland spectroscope. (You can still buy one!) With the spark from the spectroscope I was able to tease the spectrum out of elements that would rather glow in a flame and slowly oxidize than sparkle and emit their atomic line spectra. The Vreeland uses line current jumping between carbon rods to make an electrical flame that excites nearly all elements into emission.
