This wall tube was used (or was intended to be used) at the Childs power plant on the Verde River in northern Arizona. The power plant was built in 1907 to power Prescott, then Arizona's first Capital, and Jerome, a budding copper mine at that time. I found the wall tube, unbelievably, in a junk pile 50' from the power house in 1975! It appears to be a Thomas becasue of the glaze, but I am open to anyone who can tell me more. Apparently, the wall tube was never used but might have been a spare. There were several installed in the masonry power house wall but those are next to impossible to retrieve in good condition. It is in MINT condition as you can see.