Seems like someone was trying to find a product that would sink a fly - here is one by Loon - carried by Stockard.
whatever happened to Gherke’s Xink? Seems it was the standard for decades.
I never used it, I just make sure my fly is well saturated as soon as I tie it on. Never had a problem.
Get a bottle of Kodak Photo Flo. It is a lifetime supply of Xink.
http://www.amazon.com/Kodak-1464510-Photo-Flo-200-16oz/dp/B00009R7E0