Magic, Stage Illusions and Scientific Diversions, Including Trick Photography. Albert A. Hopkins
fact, indicated by a gold rod designed to hide the junction of the mirror and the side. The arrangement will be better understood by reference to the annexed diagram, which belongs to the same illusion, only the clown is substituted for the girl’s head.
Now, by virtue of the optical law that “an object reflected from a mirror appears to be behind the latter at a distance equal to that which separates it from it,” every point of the line, M l, reflected from the mirror, P M, will appear to be situated upon the line, M L.
So, to the spectator located at O, the point, c, reflected at C′ will appear to be the point, C; the distance, c C′ equaling C C′. The point, l, reflected at L′, will appear to be L. And it will be the same for all the intermediate points. The spectator, then, will believe that he sees the line, M L, when in reality he sees only the reflection of M l. Now, as we have just said, he will believe that he sees the back of the stage, when, in fact, he sees nothing but a reflection of the ceiling in the mirror. In the same way, the reflection from the front of the ceiling will produce the illusion of the stage floor. This fact still further contributes to increase the illusion, for the spectators are not aware of the difference that exists between the arrangement of the place where the bust appears and of that of the place where the showman is walking.
DIAGRAM EXPLANATORY OF THE PHENOMENON.
In the illusion of “Stella” the aperture through which the table was seen was in reality at the top. The table was vertical and the candle which was firmly fixed to it was horizontal. The farce of blowing out the candle and carrying it behind the scenes was only designed to make the spectators believe it was the same candle that was seen at the rear of the stage, when in reality it was only a duplicate.
HOUDIN’S MAGIC CABINET.
These apparatus were formerly much employed by magicians—Robert-Houdin, for instance. The following is an example of one of the scenes that may occur with them:
When the curtain rises, there is seen in the center of the stage a large, dark-colored cabinet, ornamented with mouldings, and mounted upon legs that are a little longer than those of ordinary cabinets, the object being to remove all possibility of a communication with the stage beneath. These legs are provided with casters. The showman turns this cabinet around and shows that there is nothing abnormal about it externally. He then asks some of the spectators to come up close to it, and lets them examine its interior, which is entirely empty. There is no double bottom, nor any hiding-place. When the witnesses have made themselves certain of this fact, they station themselves around the stage, and a certain number of them even consent to remain behind the cabinet and see nothing of the experiment. The cabinet being thus surrounded on all sides, and every one being able to look under it, fraud would seem to be an impossibility.
A young woman dressed as a danseuse then comes on the stage and enters the cabinet, and the doors are closed upon her. In a few moments the doors are opened again, when, lo and behold! the closet is empty, the young woman having disappeared. Then the doors are closed again, and then opened, and the danseuse makes her appearance; and so on. At the end of the experiment the witnesses examine the cabinet again, and finding nothing changed therein, are justly stupefied.
In another style of cabinet there is no bar in the center, as shown in our engraving, but there is observed on one of the sides in the interior a bracket a few centimeters in length, and, back and above this, a shelf. This arrangement permits of performing a few experiments more than does the one just described. Thus, when the woman has disappeared, the showman allows a young man to enter, and he also disappears, while the young woman is found in his place. This is a very surprising substitution.
The box into which the harlequin takes refuge, and which appears to be empty when Pierrot or Cassandra lifts the curtain that shields its entrance, is also a sort of magic cabinet.
In a series of lectures delivered a few years ago at the London Polytechnic Institution, a professor of physics unmasked the secret of some of the tricks employed on the stage for producing illusions, and notably that of the magic cabinet. The lecturer, after showing the cabinet, and causing the disappearance therein of an individual while the doors were closed, repeated the same experiment with the latter open. But, in the latter case, so quick was the disappearance that the spectators could not even then see how it was done. The illusion produced by the apparatus is the result of a play of mirrors.
MAGIC CABINET.
In the first cabinet described, when the exhibitor has closed the doors upon the young woman, the latter pulls toward her two mirrors that are represented in our plan of the cabinet by the lines, G G. These mirrors are hinged at O O, and, when swung outward, rest by their external edges against the bar, P, and then occupy the position shown by the dotted lines, G′ G′. When the cabinet is again opened, the woman placed at A is hidden by the two mirrors; but the appearance of the interior of the cabinet is not changed, since the spectators see the image of each side reflected from the corresponding mirror, and this looks to them like the back of the cabinet.
PLAN EXPLANATORY OF THE CABINET.
The illusion is perfect. When the experiment is ended and the mirrors are again swung against the sides, at G G, the spectators see nothing but the backs of them, which are covered with wood; the cabinet is really empty, and no one can discover what modification has taken place in its interior during the disappearance of the woman.
In the second arrangement, which is shown in vertical section in our last engraving, the young man gets up on the shelf, c n, at the upper part of the cabinet, by the aid of the bracket, T, and then pulls down over him the mirror, b c, which was fastened to the top of the cabinet. This mirror, being inclined at an angle of 45°, reflects the top, and the spectators imagine that they see the back of the cabinet over the shelf, as they did before.
SECTION EXPLANATORY
OF THE CABINET.
The box which Harlequin enters is based upon precisely the same principle. Its interior is hung with paper banded alternately blue and white. When Harlequin enters it, he places himself in one of the angles and pulls toward him two mirrors which hide him completely, and which reflect the opposite side of the box, so that the spectator is led to believe that he sees the back of it. In this case, one of the angles at the back of the box is not apparent, but the colored stripes prevent the spectator from noticing the fact.
A MYSTIC MAZE.
We present an engraving of a very interesting optical illusion produced with only three mirrors. By multiplying the mirrors the large number of different effects can be obtained.
Let us imagine that three perfectly plain and very clear mirror glasses, as large as possible, form a prism whose base is an equilateral triangle. A person placed in the interior of this prism will see his image reflected a very large number of times. A very simple geometrical construction, and one which we recommend our young readers to carry out as an exercise in optics, by the simple application of the principle that the angle of incidence is equal to the angle of reflection, allows us to see that the image of any point whatever placed in the center of this triangle of glass plates will be reproduced indefinitely