In 1673, French missionary Jacques Marquette was exploring the Mississippi valley when he came upon a strange mural painted on a limestone bluff near what is now Alton, Ill.:

While Skirting some rocks, which by Their height and length inspired awe, We saw upon one of them two painted monsters which at first made Us afraid, and upon Which the boldest savages dare not Long rest their eyes. They are as large As a calf; they have Horns on their heads Like those of a deer, a horrible look, red eyes, a beard Like a tiger’s, a face somewhat like a man’s, a body Covered with scales, and so Long A tail that it winds all around the Body, passing above the head and going back between the legs, ending in a Fish’s tail. Green, red, and black are the three Colors composing the Picture. Moreover, these 2 monsters are so well painted that we cannot believe that any savage is their author; for good painters in France would find it difficult to reach that place Conveniently to paint them. Here is approximately The shape of these monsters, As we have faithfully Copied It.

In 1836 local settler John Russell told of a flying monster that lived in the cliffs and attacked nearby Indian villages, and the notion of wings is carried through in the reproduction above. Because the original is lost, we can’t be sure how faithful it is.

Thomas Jolley Death has a brother named Sudden Death, as the former told when he was on a professional visit to Nottingham, Eng., as a private detective. The father of the two men may yet be alive, and if so, has probably had time to reflect upon the hideous names with which he labelled his two baby boys to go through the world. The real name of the family is D’Ath.

— Bizarre Notes & Queries, April 1886

Add these numbers aloud:

When you’re certain of your answer, confirm it with a calculator.

Most people find they’ve made a mistake.