Gas Line "Flame"

This box with the stylized flame is on a street on my route to work. I think it was a control box for the gas company (and as you may know, the local gas company, PG&E, has been in the news for corroding underground gas line infrastructure, resulting in explosions and fires). The flame must have been a way to demo both the purpose and the risk of the gas lines at some time earlier in the 20th century....or today.