Lovely gas fired A/H vent

I thought the circa 1920s home had been updated and cared for pretty well until I found this gas furnace vent in the crawl space!

And single wall in the crawl space at that…

Well why waste all that warm air, Probably no critters living down there

Well at least it was in the crawl mine was in the home utility room and had this black stuff to go along with it talk about indoor air quality:shock::shock: