How would one generate static electicity in medieval period? [closed]

Question

My magic system require a source of elemental magic, fire spell would consume the energy from the caster body, so throwing fire ball would eventually tired the caster out.

Now electricity would also require a source, the human body could generate weak electricity since it's how our nervous system function but it's probably not going to do much harm other than giving the victim some sharp pain, maybe touching the chest of the victim while casting the spell might give them a heart attack..

So for larger lighting spell, one would need wait for thunderstorm to arrive.. but the caster still need to learn and practice how to grab the electricity from thundercloud..

The answer is static electricity, after some googlings, I discover that cat fur is great for holding on static electricity which are great since in my story, there is a catgirl companion that is covered in fur, so I can use her to store electric charge for my character to practice the spell in small scale..

But the problem is, I can't get a clear answer on what material to rub on cat fur to generate static electricity, since it take place in medieval fantasy, my selection on material is limited to wool, cotton, linen, leather and glass.

So which material should I use to get static electricity from cat fur?

I hope someone here can help.

Answer 1

Although it's tempting to keep the physics of your world 100% accurate, remember that you're writing a story that contains magic. For this reason, you can have your characters generate static electricity in any way that seems clear, convenient and plausible to the reader. Leather or wool against a cat seems like a great option.

In general, most readers won't conduct research to see if it actually works. Just focus on making it sound believable and interesting!