Andrew Lang,
Cock Lane and Common-Sense
“ That spirits should knock and rap seems to us about as improbable an idea as could well occur to the fancy. Were we inventing a form for a spirit’s manifestations to take, we never should invent that. But what a savage might think an appropriate invention we do not know. Meanwhile we have the mediæval and later tales of rapping, some of which, to be frank, have never been satisfactorily accounted for on any theory. But, on the other hand, each of us might readily invent another common ‘manifestation’—the wind which is said to accompany the spirit. ”
