The round thingys in a wood/coal burning stove are called “stove lids” and the handled thingys are called “stove lid lifters”. The reason the stove lids are round is so they can’t fall through the hole in the stove. Stoves were made with 1, 2, 4 or 6 stove lids depending on the size of the top surface.
The reasons a stove was made with “lids” are:
1). to add fuel or dispose of trash/garbage.
2). the casting process, for cleaning and/or to reduce the weight of the stove when moving it, and
3). for removal when cooking or heating …… which I’ll explain by the following 2 pictures and a url link:
The 1st pic is of a cast iron griddle and if you ever wondered why it was made in that shape then look at the 2nd pic of the stove top. If you remove the 2 stove lids on the left side and the spacer between them ….. that griddle will sit right down in the opening (that is iffen it’s the right size).
And if you click on that url you will see a cast iron tea kettle with a “raised ring” around the bottom of it which is probably 3/8” high and ¼” wide. And like the griddle, if you remove 1 of those stove lids that tea kettle will sit right down in the opening (that is iffen it’s the right size).
griddle
cookstove
Tea kettle
http://cgi.ebay.com/ANTIQUE-CAST-IRON-TEA-POT-KETTLE-LID-6-/300515960761?pt=LH_DefaultDomain_0&hash=item45f825a7b9