Is This the Oldest Commercial Heat Treater in North America?

We were speaking the other day with John Quaglia, President of family owned Bennett Heat Treat which has two locations, one in Newark, NJ, USA and the other in Ivyland, PA During the course of our conversation it came up in passing that the company has been in business since 1923 making it 95 years old-quite a feat. This prompted the question-is this the oldest commercial heat treater in North America?¬†Certainly we can’t think of one older and neither could John. If anybody knows of an older shop we would be interested in hearing about it.