The board that is employed in this case, instead of being, as in the genuine performance, a simple one, is a piece of cabinet work containing an ingenious mechanism. The place which the human target will occupy on this board is carefully marked, and the knives that are to be stuck into the board in succession around such place are contained in the cabinet work, which, at first sight and at a short distance, seems to be absolutely without preparation.
Each of these knives is fixed by its point upon a pivot. In addition, it is controlled by a spring, and is concealed within the board by a very finely adjusted double-valved window, which, at the proper moment, opens and allows it to appear, and then closes. The spring causes the knife to fall or rise according to the place that the latter is to occupy. No. 2 of the [engraving] shows the window opening to allow of the fall of the knife, which will appear as if stuck into the board just above the instep. In each of the valves the angles that meet each other are cut slopingly either at the top or bottom, according as the knife is to fall or rise, in order to make space for the blade when the valves are closed. Before the exit of the knife, the incision is closed with modeling wax the color of the wood. In our engraving the incision is at the bottom.
Naturally the knives are concealed in the board in such a way that on making their exit the field shall be free, and that they shall not come into contact with the limbs of the target. Each of these knives, with its window, forms a distinct apparatus, which is controlled by a rod that ends at the edge of the board just at the place where the fingers of the human target can reach them. It is he who, by pressing upon the ends of the rods as if upon the keys of a piano, causes the blades to come out of their place of concealment, one after another, and appear as if they had just stuck into the board. The sound made by the spring in expanding and the sudden appearance of the knife, combined with the motion of the person throwing it, affords a complete illusion. Let us add that each knife mounted on a pivot at its point, as we have explained, may be easily disengaged from its axis when, after the operation, the person who threw the knives makes believe to pull them out by force from the wood in which they seem to be inserted.
The board having been invented, it became necessary to find a method of throwing the knives in such a way as to cause them to disappear. To this effect the board is placed on one side of the stage, near the side scenes, and the person who throws the knives stations himself on the other side of the stage, near the opposite side scenes, and he can therefore act in two ways, viz., first, in poising his arms to take aim, he can, at the last moment, throw the knife between the side scenes back of him while he takes a step forward. The knife supposed to be thrown thus disappears completely at the desired moment, but, since the spectators do not see the flash of the blade, traversing the stage, it is preferable to employ the second method. This consists in a genuine throwing of the knife, but in such a way as to cause it to pass by the board and fall between the side scenes, where the sound of its fall is deadened by some such material as a piece of carpet. In both of these two methods, it is for the human target to press the spring of the knife that he wishes to make appear at just the precise moment, in order that the click of the expanding spring may be taken by the spectators for the sound of the knife sticking into the wood.
This trick, when well executed, has often deceived the shrewdest spectators, and that, too, with so much the more facility in that many had seen the Japanese perform in the middle of a circus, where it was impossible to conceal the knife, since it could be followed by the eye in its travel from the hand of the Japanese to the point where it penetrated the board.
To be precise, and to omit no information, let us say in conclusion, that there exist boards in which the freeing of the knives is effected by the pulling of a thread held in the side scenes by a third party. This process has the advantage that there is no danger of the spectators seeing the manipulation of the rods; but, on the other hand, it has its inconveniences, viz., in a place where a communication cannot be established between the invisible confederate and the mechanical board, the use of it is impossible, and it is necessary to employ the other method.
SWORD SWALLOWERS.
When a physician introduces his finger, the handle of a spoon, or a pencil into the throat of a patient, the latter experiences an extremely disagreeable sensation. Any touching of the pharynx, however slight it be, causes strangling, pain, and nausea, and the organ reacts with violence against the obstacle that presents itself to free respiration. There is no one who has not more than once experienced this disagreeable impression, and for this reason we are justly surprised when we meet with people who seem to be proof against it, and who, for example, introduce into their pharynx large, solid, and stiff objects like sword blades, and cause these to penetrate to a depth that appears incredible. It is experiments of this kind that constitute the tricks of sword swallowers.