I have an old framed drawing or sketch of what looks like a black/Indian hunter on a horse which to me looks like an Arabian. It is on a sort of cardboard type medium and the entire piece with detail (horse's muscles etc.) was pushed out from the back of the medium so it is dimensional! It is truly Amazing and very old. I would love to email a picture to anyone who may have any thought on this. FYI; in the lower right corner is something written but barely visible to the eye.. Abby? George? Very difficult to make out.
Thanks for any help with this mystery.

Here is the picture in question. The entire thing is pushed out from the back! Amazing.