An axe gauge is a small tool with a triangular cut out used to measure the profile of an axe blade. Axes have different profiles for different jobs. For example, a splitting axe can be nearly triangular in shape, while a limbing axe has a much more narrow profile. Gauges were used to set and maintain the optimum profile for a specific job. Once common, now they are few and far between.
Years ago at the Snow Walker’s Rendezvous I got my hands on a photocopied sheet from an old book showing the shape of several different axe gauges. It was from an old book that Geoff Burke had come across or once owned, I can’t remember the whole story. Geoff had a lot to do with the genesis of the Gransfors American felling axe (more on this here). Anyway, he had this photocopy several different axe gauges on it. I found it in a file cabinet recently and scanned it. You can get a .pdf copy at:
http://www.jackmtn.com/PDF/axe_gauge.pdf
Please download it and repost it on any forum you frequent.