What is Grinding Wheel?

A wheel that grinds.

A bit like Beyonce, but more circular.

I don't believe i've ever heard anyone use the term grinding wheel, but i suspect it means the same as a grindstone:

That takes me back.

When I was a pre pubescent trainee butcher, the old boy who worked at busting down beef sides all day used to tip me the wink occasionally, and steal me away from the shop floor so he could sharpen his full set of knives.
The shop had an old outhouse at the end of the rear yard, which housed a grindstone just like the one in your picture.
We'd disappear down there with a steaming mug of coffee each, and I'd wind the handle while he'd sharpen the blades.
The wheel itself sat in a shallow trough of water at the bottom, so it would automatically wet itself, if you'll pardon the expression.
In between knives, we'd sit and smoke, and he used to tell me the most outrageous stories from when he was in the army.
His knives would end up sharp, my biceps would end up a tad larger, and I'd learned a few more things about French women.


Happy days.

There was a cartoon with a viking bragging how very sharp he had gotten a knife by using a grinding wheel.

The reply was that it should be sharp as you began with a six foot long sword.

My grandfather had a grindstone, but it was table-sized. He had mounted it to his workbench, and like almost everything around the house, he had added an electric motor. (He apparently went through a phase of mounting electric motors on every thing--in the 1920s.) His had a little cone-shaped attachement above, as in that illustration, which dripped oil onto the wheel when you turned a spigot. He took to removing the fuse in the main junction box in the house when he found that we were going into the shed, turning on the wheel, and opening the spigot to watch the oil fly. We were little stinkers.

You can use a stone with either oil or water.
And, you can change a wet stone to an oil stone, but not the other way around.