Not all mysteries in the world lead to glorious revelations. Some of them are a bit more humble. One enduring scientific mystery is the earliest form of sneezing powder. A fortune was built on this special formula, but when it was found to be toxic, it was recalled. Its inventor refused to ever identify what it was, but some people say they know.
I've never liked pranks. To me, they're just mean things that people do to you when they suspect you're too beaten down to yell at them for it. But S. S. Adams liked a prank or two. He eventually amassed a huge fortune selling joy buzzers, flowers and cigarettes that squirted water. To start it all out, though, he marketed sneezing powder. Today, sneezing powder is likely to contain hellebore - an herb found to be an irritant. It's even more likely than that to contain nothing whatsoever, since even hellebore has been known cause fainting and heart problems while an ineffective product is found to cause little more than a few minutes of emotional irritation.
Adams, however, went all out. He tested his product on rooms full of executives, and blew it into the path of marching bands. Both had to stop for minutes until the sneezing fit cleared up. It's lucky that Adams made a small fortune with Cachoo sneezing powder in the relatively short time between 1904, when it was put on the market and 1919, when it was banned by the FDA - because he would almost certainly have had to move away from the people he tested it on. He never revealed what his formula was.
No one's entirely sure what Adams used to make Cachoo. It depends on what he had easy access to. He worked for a company that made coal tar products, specifically dyes. Coal tar is what gets leftover when coal is made into more purified fuel. It's a viscous black substance that can be used to pave roads, but is also added to medicated shampoo, and used as a base for clothing or even food dye. There are plenty of by-products in the process that can - but probably shouldn't - be used as nasal irritants. These would be easily accessible, and, if they were by-products, cheap to acquire.