Travis Industries 1080 Owner's Manual page 18

Preparing the Rock Wool:
The rock wool comes in one
clump. Tear off "dime" sized
clumps and flatten. Then pull on
the wool to create gauze-like
pieces. The wool glows best
when very thin and porous.
Place small pieces of rock wool next to the burner holes in
visible locations. Place the rock wool sparingly so it does
not cover large areas of the burner.
WARNING: If the rock wool is too thick or placed so it
obstructs the flow of gas, sooting will occur.