A Antique Grill Pan
Thanks for posting that. I believe it's made to sit where a wood cookstove's lid would. Some fat drips into the fire, but much of it is caught and collected in those channels. I have a rectangular one, but it is flat whereas yours appears to be convex--even better for draining away the fat.
These aren't a lot of use on modern hobs, though. Maybe over a campfire?
What's the diameter of the pan?
You're probably right about the wood stove. They were called smokeless grills because the grooves caught all the fat. The pan is 10" in diameter and I use it all the time.
Mostly under the broiler but if you want something really
seared put it over gas and get really hot keep turning the
meat to keep from sticking. Ed