This section is from the book "Hypnotism And Hypnotic Suggestion", by E. Virgil Neal, Charles S. Clark. Also available from Amazon: Hypnotism And Hypnotic Suggestion.
After you have secured, as much as possible, the confidence and willingness of the person with whom you are about to experiment, request him to stand in front of you with his eyes closed, his feet together, and his arms hanging loosely at his sides. Tell him to try to think what it would feel like if he were falling over backward. Ask him not to try to fall, and not to resist the tendency to fall. Explain to him that there is no possible danger in this, and that if he should fall you will catch him.
When you are certain he understands you perfectly, take your. position back of him, and, using both hands, gently stroke his forehead from the middle, back toward the sides. Continue this slow stroking for some time, suggesting at the same time, in a low, monotonous tone, "Now you feel like falling - you find you are coming over backward; back-back-back." Vary the stroking of the forehead by running your finger down the back of the head until you reach the hollow part of the neck. Press on this a little and then gradually pull the finger away and downward.
In many cases you will find by this time a tendency to sway over backward. Some will simply sway and will resist; others will fall suddenly; a few will seem not to be affected at all. If you are not successful on the first trial, make another attempt. With repeated trials you will find that a very large proportion, of those you try will tend to fall backward.
It sometimes happens that when they fall backward they keep their eyes closed and seem to be asleep. If this is the case, simply clap your hands together, or snap your fingers, and say in a decided tone, "All right!" Very few of the subjects, however, will go to sleep in this experiment. They are not hypnotized in the sense we generally use the word, although they are unconsciously acting out your suggestion.
 
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