Conan Doyle works on our prejudices in another way, too, by setting his novel on the “primitive” landscape of the moors. We are told: “When you are once out upon [the moor’s] bosom you have left all traces of modern England behind you, but, on the other hand, you are conscious everywhere of the homes and the work of the prehistoric people. On all sides of you as you walk are the houses of these forgotten folk, with their graves and the huge monoliths which are supposed to have marked their temples.” The escaped convict Selden, who is described as being “a wild beast” and having “a terrible animal face” could represent civilization’s fear of the return to a primitive stage of humanity. Linguistically, we yoke all these words together: “prehistoric,” “nature, “wild,” “beast,” “animal,” “supernatural,” and “superstition.”
Conan Doyle set the novel in such a place to draw both the reader and the characters out of reason and skepticism, if only briefly. The fog threatens Holmes’s plan and Sir Henry’s life, in fact it is “the one thing on earth” that could. The Grimpen Mire is a sort of primitive place within an already primitive place, allied with the supernatural and considered to be an enemy of Holmes and order. In this arena, irrational thought might actually defeat Holmes’s machine-like, scientific mind. But primitive nature in the form of the Grimpen Mire also swallows Selden and Stapleton into its depths, spelling doom for agents of science and agents of superstition alike.
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