Went through about 300 air compressor ads that date back to 1913, not one Fero.
Possibly a very small company but they didn't do much advertising, nothing in National Petroleum News, Motor, Motor Age, Motor Life, Super Service Station, etc.
Mr. Timmins mentions that Brummer was one of their largest competiors. I have probably 75+ ads from Brummer, and actually Brummer's largest competitor was Curtis from right hear in St. Louis (also have about 75 ads from Curtis).

One more thing I want to mention, and it has nothing to do with the above, finding an old air comprressor today does not mean you have found an old air compressor.
Some you might remember my post where I had dragged home an old 1947 Curtis a/c. Well, after looking up the compressor in my literature I discovered that the only thing Curtis that was left was the tank. The motor was now a Dayton, not a Curtis, the a/c itself was also not a Curtis, it have been repalced with a Dresser (the company that owns the Wayne Pump Co. today). Things wear out and who knows what they are replaced with.

Jack Sim

Author, 1st & 2nd editions of Gas Pump ID book, 3rd edition is now available at www.gaspumpbible.com
Air Meter ID book also available