Good Question Mary...! One that could lead to the opening of a big can of wormees which I refuse to get the can opener out for..lol

Micca is correct about one of the source's where the "essence" can be found but that would be Black Market Essence of Scottish Nutter, bloody potent stuff and let me tell you there is no better place to find the most powerful of this essence than at the Saracen Head Pub in Glasgow (or as the locals call it 'The Sarry Heid' pub).
There is a lady that lives in the pub. She is called Maggie. She has been there for oh, a few hundred years (even moving location with the pub)..Maggie will put your right on the 'Essence'...

Now what with it being Friday, I have a few things to do. I shall however return later this evening with some news from the OPU and the info on the fall courses available.

Eh, I tried the 'Spell' spell Leeneia, but maybe my dizzylexia posed a problem...my Horse has turned into a Weasel. Any ideas on reversal!

Dancing, Dumplings, Flouncing and grumblings
J