I did not need glasses as a kid, but I can still smell things way before others. As you describe it, I can smell the edges of the scent trails, as it fades and

I did not need glasses as a kid, but I can still smell things way before others. As you describe it, I can smell the edges of the scent trails, as it fades and gets stronger. I understand why dogs sweep back and forth; they are trying to find the edges and help them move the direction of the trail.