"But, how could you know? I did not make a noise or display my presence in any way."
"No!—but the wind was blawin' from the back, ye see; and when ye came up behind the smoke curled up a bit further and straighter than it did before; then there was just the ghost o' a shadow."
I laughed. "You are an observant customer."
"Oh, ay! I'm a' that. Come round and let me see ye."
I obeyed, and he seemed satisfied with his inspection.
"Sit doon,—oot o' the smoke," he said.
I did so.
"You are Scotch?" I ventured.
"Ay! From Perth, awa'.
"A Scotch tinker?"