Who says nothing good happens when you suspend a bowl of water above a beer vat?
Not Joseph Priestly. Back in 1767 he invented a way to carbonate water by suspending it above fermenting beer. At the time, the air blanketing the beer was known to kill mice. But Priestly figured out that this carbon dioxide would also infuse into the water and turn it into something similar to the naturally carbonated "spa" waters that doctors of the day thought had curative properties.
Certain rare geological conditions like volcanoes create springs that produce naturally carbonated water. For the rest of us who don't live near a volcano and aren't a scientist, there wasn't a way to get carbonated water until a Swiss watchmaker named Jacob Schweppe read about Priestly's discovery and invented an artificial mineral water making machine. He called it the Geneva Apparatus (next band name, anyone?) and it produced water with more aeration than in the natural mineral waters. The carbon dioxide came from a mixture of chalk and sulphuric acid. But this gave the carbonated mineral water a slight acid taste, so he added a dash of salt to make it taste better.
Doctors of the day soon proscribed the carbonated water neat for a variety of aliments such as "Stone of the Bladder". However it didn't hurt that the salt in the Schweppe's mineral waters also masked the impurities in whatever it was mixed with. So patients soon added the carbonated water to their own self-medications. The "dash and a splash" was born. It quickly had many siblings.