Isn't he a handsome fellow? I found him in the August 8, 1913, edition of The Bemidji (Minnesota) Pioneer.
I love finding Airedales in ads, no matter the year. I know they were very popular in the 1920s but I hadn't realized that they were already popular in the 19-teens. These days it's uncommon to see Airedales in ads -- but I know all ADT lovers perk up when we see them.