edit: Erp. Ignore below. Precipitate took a while to form, I suppose. Narmz mentioned the fumarate takes a little while to drop out of d-limonene, so perhaps the same is true for HCL out of xylene. There is some beautifully sparkling white, very fine crystals covering the bottom of the jar. I'm sure they will come out stained and a wee bit smelly, but I'm sure they will clean up just fine! Perhaps I'll report back with yields.
Added 50 ml of HCL saturated acetone into the weakest of three 800 ml xylene pulls. There was the equivalent of 1/3rd of a mL of 33% HCL acid solution in the 50 mL of saturated acetone. No precipitate resulted.
Did I use too little HCL? I figured maybe the epsom salts pulled it out of solution or something but I can still see it swirling around in there like heat in the distance. Surely that was enough for something to precipitate. I suppose there is a possibility the acetone didn't dry properly. In which case there would be something like 2.5 mL of water in the acetone (holds about 5% at stable, I think, so 5% of 50 mL). That would only explain the loss of some of the precipitate, though I have no idea how much mesc hcl is soluble in water.
What does that mean? I'm going to try some vinegar pulls on them or something I guess. I don't see how nothing could precipitate. D'oh. The jar was 3/4ths the fourth pull and a wee bit poured in from the third pull, so there definitely shouldn't have been much mescaline in there, but there should have been something!
Anybody have any insights?