The Blog of the Unknown Postcard

I need your help. I've been page by page through the 2009 Standard Catalog of Baseball Cards, and I can't identify this. More precisely, I can't identify the player, the team, or the issue. I have a pretty good idea what era it's from (pre-1919), but even of that I'm uncertain.

Some background: I've had this postcard at least 20 years. I can't remember exactly where I got it, but either a family friend who collected postcards and knew I liked baseball stuff, or from the Big Box of Awesome Tobacco Pins I inherited from my great-grandfather. Also, it's the size of a regular postcard, not a cabinet.

That's all I know about it. My guess is that the uniform is from one of these types: industrial team, an amateur team, or some sort of low minor league. I've never seen any other cap with a number on it like this, nor do I have any idea what the "CAD" down the front of the flannel stands for. The back is almost blank, which isn't helpful, and there's no photographer's seal or trademark anywhere on the card, which isn't helpful either, but leads me to think this isn't part of a large (or any) set.

So, what do I have here?