On Fri, 25 Sep 2009 09:18:34 -0400, JustWait
wrote:

I tried to get some Salt Peter for smoking meat. My FIL used it as a
preservative. The pharmacy said they could get me some, then a week
later changed their mind. By the conversation, I assumed "somebody" else
changed their minds for them...

Saltpeter is potassium nitrate, a key ingredient of gunpowder among
other things. It can be ordered online.

http://www.skylighter.com/potassium-nitrate.html