lay.

"As I reclined," he says, "my eye fell upon the glass, and I saw two
images of myself, exactly alike, except that one was a little paler
than the other. I arose and lay down again with the same result. It
made me quite uncomfortable for a few minutes, but some friends coming
in, the matter passed out of my mind.

"The next day, while walking in the street, I was suddenly reminded
of the circumstances, and the disagreeable sensation produced by
it returned. I determined to go home and place myself in the same
position--as regards the mirror--and if the same effect was produced,
I would make up my mind that it was the natural result of some
principle of refraction or optics, which I did not understand, and
dismiss it. I tried the experiment with the same result; and as I had
said to myself, accounted for it on some principle unknown to me, and
it then ceased to trouble me. But the God who works through the laws
of nature, might surely give a sign to me, if one of His chosen
servants, even through the operation of a principle of optics."

This, seeing one's simulacrum, or double, was so common, especially
when looking-glasses were full of flaws, designedly cast faulty to
give "magical" effects for conjurors, that old books on the black art
teem with instances. Lincoln was right to demonstrate that the vision
was founded on fact, and no supernatural sight at all. His trying the
repetition was like Lord Byron's quashing a similar illusion, but of a
suit of clothes hung up to look like a friend whom he believed he saw
in the spirit. A more widely read man would have dismissed the "fetch"
like the President-elect, but with a laugh.