We didn't get things to gel, but ...
I was up north a little over a week ago, teaching horse people, and they wanted a liniment that was a little less liquid: something which wouldn't run off the hand right away.
We'd made tinctures with suitable herbs the previous time I was up there, weeks earlier, so we started by straining those. (Suitable herbs for a liniment include Filipendula, cayenne, spruce shoots, black pepper etc. - liniments are usually used for aches or for cold or sore muscles.)
We'd made the tinctures from dried herbs and store-bought vodka, 38 %, which is a tad on the low-alcoholic side.
And a mix of equal parts of alcohol, water and oil should make a thicker liquid.
One of the ladies remembered that you can make this by adding the oil in a thin stream to the alcohol + water part (= our tincture). No trouble, just get to it; no real kitchen, though, so we whisked things with a fork.
Result # 1: If you add oil to the water+alcohol the two won't mix.
This was not a problem, as we had another jar of the same tincture, so next we did things the right way around, and added alcohol+water in a thin stream to the oil, whisking all the way.
Things looked extremely good, until right at the end, when the liquids separated - now liniments #1 and #2 looked exactly the same. Shaking the jars would bring them back into a thicker liquid, but they didn't stay that way for very long.
In fact, both were pretty much useless for linimentary purposes.
We thought that this was maybe due to the lack of advanced implements, and got in a handheld whisking thingy.
You can redo a lot of separated mixtures just by starting to whisk them into whatever it is you're mixing things into; in this case, we put a dash of oil into a bowl and added our separated liniments in a thin stream, whisking all the time.
They separated again.
Result # 2: Things won't stay set the other way around either; it's possible that we had too much water and too little alcohol in our blend.
Hmmm, let's see what happens if we firm up the watery part of the mix. The local pharmacy didn't have any pure pectin (and said that they couldn't get any the last time they tried, about a year earlier), but the local shop had various preserving mixes. We used red melatin, which contains sugar, carrageen (E407), carob flour (E410), sodium benzoate (E211) and potassium sorbate (E202).
So we carefully warmed up yet another jar of tincture, with no oil mixed in yet, and added in the gelling/preservative powder.
The result was rather stringy, because our watery mix included alcohol. No problem, just start mixing this into an oil base again ... now those strings broke up to make tiny translucent globs, and the resulting liquid stayed firm.
Result # 3: Firming up the watery-alcohol part works, but the resulting mix doesn't look all that good.
While discussing the results of this (and a few other experiments) over a coffee break, somebody brought up the idea of adding beeswax to the mix.
Right, then, heat the oil on a waterbath, add some (not much) beeswax and put the stove on full until the wax has melted, then start to add the tincture (previously heated (or not) to about 60 deg. C) in a thin stream, whisking all the while.
Result # 4: Firming up the oily part works. Woot! And there's no need for preservatives.
We added tar to one batch (mmm for that scent!) and heating spices to another (cayenne, mustard, ginger and black pepper).
Oh, and what else did my students learn this time? They said they'd have thrown out the various tries at liniments the first time they failed to combine. I guess none of them have made mayonnaise, where, if things separate, you just start to whisk your separated stuff into yet another egg yolk, and you're possibly more careful about it: don't let things drip into the mix all that fast, and mix mix mix all the time.