The Little Geogia Wonder Notes:

The pole trick explanation:

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Two men (Fig. 2) take a stick about three feet in length, and are asked to hold it firmly in a vertical position. The girl places her hand against the lower end of the stick, in the position shown, and the two men are invited to make the latter slide vertically in the girl's hand, which they are unable to do, in spite of their conscientious and oft-repeated attempts. Mr. Perry explains this exercise as follows: The men are requested to place themselves parallel to each other, and the girl, who stands opposite them, places the palm of her hand against the stick and turned toward her. She takes care to place her hand as far as possible from the hands of the two men, so as to give herself a certain leverage. She then begins to slide her hand along the stick, gently at first, and then with an increasing pressure, as if she wished to better the contact between the stick and her hand. She thus moves it from the perpendicular and asks the two men to hold it in a vertical position. This they do under very disadvantageous conditions, seeing the difference in the length of the arms of the lever. The stress exerted by the girl is very feeble, because, on the one hand, she has the lever arm to herself, and, on the other, the action upon her lever arm is a simple traction. When she feels that the pressure exerted is great enough, she directs the two men to exert a vertical stress strong enough to cause the stick to descend. They then imagine that they are exerting a VERTICAL stress, while in reality their stresses are HORIZONTAL and tend to keep the stick in a vertical position in order to react against the pressure exerted at the lower end of the stick. There is evidently a certain vertical component that tends to cause the stick to descend, but the lateral pressure produces a sufficient friction between the hand and the stick to support this vertical force without difficulty. Mr. Perry performed the experiment by placing himself upon a spring balance and assuming the role of the girl, with two very strong men as adversaries. All the efforts made to cause the stick to slide in the open hand failed, and the excess of weight due to the vertical force always remained less than twenty five pounds, despite the very determined and sincere stresses of the two men, who, unbeknown to themselves, were exerting their strength in a HORIZONTAL direction. In the experiment represented in Fig. 3, which recalls to mind the first one (Fig. 1), the two men are requested to hold the stick firmly and immovable, but the slightest pressure upon the extremity suffices to move the arms and body of the subject. Such pressure in the first place is exerted but slightly, and the stresses are gradually increased. Then, all at once, when the force exerted horizontally is as great as possible, and the men are exerting their strength in the opposite direction in order to resist it, the girl abruptly ceases the pressure WITHOUT WARNING and exerts it in the OPPOSITE DIRECTION. Unprepared for this change, the victims lose their equilibrium and find themselves at the mercy of the girl, and so much the more so in proportion as they are stronger and their efforts are greater. The experiment succeeds still better with three than with two men, or with one man.