Barium was discovered by Sir Humphrey Davy in 1808. It is toxic to humans if ingested as a soluble salt in the form of barium chloride and can cause heart problems. When used in the insoluble form barium sulfate, it provides radiologists x-ray images to examine the digestive tract. Barium was also widely used in vacuum tubes to remove unwanted gases and moisture. Being a big fan of the pyrotechnic convention that comes to the Fargo area every three years, I preferred to depict barium as used to produce the green color in fireworks.