Trail Signs

I have a book called "Signs and Signals" by Catherine Davidson. This is a book outlining some basic forms of communications using signs and signals, obviously, like sports hand signals or sign language. One section that I thought would shed some light on signs along the trail ended up confusing me more.

















As a brief intro stated, some of these signs might be made out of objects found along the trail. Interesting to think of how to display a message using found objects and how they really work only with found objects. As 2-D symbols representing how they would be seen along the trail the signs, three out of four, seem misleading especially because the arrow (the main clue) would not be there. If I was on a trail and said "look a trail signal" and saw the found objects arranged so I would probably get it, mostly because it is one of a handful of messages that would want to be communicated. Now how to recognize when there is a sign versus nature's own fate or displaying a more complex message like "rattlesnake wielding mountain men below" I have no idea.