Here follow two excerpts from John Harland and T.T. Wilkinson’s 1867 book on Lancashire Folk-Lore. The book can be downloaded here.
This word, derived from divinare, to foretell, denotes a mode of foretelling future events, and which, among the ancients, was divided into two kinds, natural and artificial. Natural divination was prophecy or prediction, the result of supposed inspiration or the divine afflatus; artificial divination was effected by certain rites, experiments, or observations, as by sacrifices, cakes, flour, wine, observation of entrails, flight of birds, lots, verses, omens, position of the stars, &c. In modern divination, two modes are in popular favour—thrusting a pin or a key between the leaves of a closed Bible, and taking the verse the pin or key touches as a direction or omen: and the divining-rod, a long forked branch or twig of hazel, which being held between the finger and thumb in a particular way, is said to turn of itself when held near the earth over any hidden treasure, precious metals, or over a spring of water. It has also been used to discover a buried body of one murdered.
DIVINATION BY BIBLE AND KEY.
When some choice specimen of the “Lancashire Witches” thinks it necessary to decide upon selecting a suitor from among the number of her admirers, she not unfrequently calls in the aid of the Bible and a key to assist in deciding her choice. Having opened the Bible at the passage in Ruth: ”Whither thou goest will I go,” &c., and having carefully placed the wards of the key upon the verses, she ties the book firmly with a piece of cord, and having mentioned the name of an admirer, she very solemnly repeats the passage in question, at the same time holding the Bible suspended by joining the ends of her little fingers inserted under the handle of the key. If the key retain its position during the repetition the person whose name has been mentioned is considered to be rejected; and so another name is tried, till the book turns round and falls through the fingers, which is held to be a sure token the name just mentioned is that of an individual who will certainly marry her. I have a Bible in my possession which bears evidence of having seen much service of this description.