CAPÍTULO 3. ANÁLISIS DE RESULTADOS Y VALIDACIÓN DE LA PROPUESTA
3.2 Aplicación de encuestas al Equipo de Desarrollo
Figure 26
The requirements for this feat are a carafe of water, duly prepared, six wine-glasses on a tray, and a small glass funnel.
To prepare the carafe, the performer must provide himself with aniline dyes (in powder) of six different colours; say, crimson, blue, violet, orange, scarlet, and green. Mixing glycerine and water in equal proportions, he moistens therewith a minute quantity of each of the colours, rubbing it down to the consistency of cream.
We will regard the glasses as being numbered, according to their order on the tray, 1, 2, 3, 4, 5, and 6. Of these, Nos. 1, 5, and 6 are left unprepared, but the other three each have at bottom a little dab of one of the pigments, crimson in No. 2, blue in No. 3, and violet in No. 4.
Similar little dabs are applied to the lip of the carafe (see Fig. 26), orange at the point a, scarlet at b, and green at c. The opposite side, d, of the lip is left open.
With this preliminary explanation, the working of the trick will present little difficulty. In filling glasses 1, 2, 3, 4 (as also in the preceding tricks if the same water is used for them), the performer takes care so to hold the carafe that the water shall pass out over the unprepared side, d, of the neck. The natural result is that the water in glass No. 1 remains clear, while that in Nos.
2, 3, and 4, dissolving the pigment therein, becomes crimson, blue, and violet respectively. After pouring back the water in glass No. 1 (which he does by means of the funnel), he fills the same glass again, but this time pours the water out over the point a, thus producing orange colour. By pouring out over b and c respectively, he produces scarlet and green in the two remaining glasses.
The addition of a little whisky or rectified spirit to the water, in the proportion of about one part in eight, is recommended as tending to make the colours dissolve more quickly.
19-20. The Mysterious Addition.
This trick is really two tricks in one, consisting of (1) the discovery of the total of the three numbers, and (2) the production of such total, in a magical way, upon the slate. It will be convenient to discuss them separately.
It is humiliating to have to confess it, but the performer, even with the assistance of any number of fairy godmothers, is wholly unable to discover the total of the three numbers written down by the three spectators. What he actually does is to disclose the total of three numbers previously written down by himself. Each such number, of three figures, is written in pencil on a card, the size of a gentleman's visiting-card, in a different style; say, one bold and heavy, one faint and scratchy, and the third in rather minute characters. We will suppose that the numbers decided upon are 730, 551; and 304, making, it will be observed, a total of 1585. Each card is folded in half, and the three are placed in a small envelope, about an inch and a half square, such as is frequently used , in shops to enclose the customer's " change." This the performer may place on his table, or a side table; with a second envelope, of similar appearance, but empty, laid upon the top of it. Close beside these should be laid three blank cards to correspond, and three pencils.
When he proposes to show the trick, the performer picks up with the left hand the pencils and the three cards, and with the right the two envelopes (as one); the prepared one, which was undermost, coming naturally next to the fingers. By means of a little manipulation, which the novice will readily discover for himself upon experiment, the prepared envelope may be drawn back so as to rest inside the hand, against the second joints of the second and third fingers, in which position it is an easy matter to keep it concealed from the spectators.
The pencils and cards are distributed, and three numbers, each of three figures, duly written. The cards, folded in half, are placed in the empty envelope. The performer then asks who will represent the Grand Panjandrum, and add up the figures. While waiting for some one to volunteer, he holds up the envelope just received between the fingers and thumbs of both hands, in so doing getting the envelope containing the known numbers in front of the other, which is then pushed by the left thumb into the right hand, in the position previously occupied by the prepared one. The envelopes are thus "changed," and it is the numbers on the cards in the latter which are really added up.
The second portion of the trick consists of the revelation of the sham total, by producing it upon the apparently clean slate. There are many ways of doing this, and I must content myself with describing two of them, one with a prepared, and one with an ordinary, slate.*
The "slate" used for this purpose is generally not made of slate at all, but of carbonized mill-board, on which a slate-pencil writes with equal facility, and which is very much thinner and lighter than slate itself. The use of this material excites no suspicion, inasmuch as what are known as "memorandum" and "book" slates are habitually made of it. The trick slate in its simplest form consists of a slab of this material; framed in the usual way, with a loose slab to correspond lying over it within the frame, and so covering over any writing which may be upon it. Both of the visible surfaces may be cleaned as freely as the performer pleases; after which, by getting rid of the loose slab, he can expose the hidden writing.
The problem is how to do this without the knowledge of the spectators. To that end, the inner surface of the loose slab is sometimes covered with the same material as that of the table-cover, on which it may therefore be allowed to slip out, without attracting observation. Another
* For further information on this subject, the reader is referred to an excellent little work by Mr. W. E. Robinson, Spirit Slate Writing and Kindred Phenomena. London: Sampson Low, Marston & Co.; New York: Munn & Co.
plan is to have the inner surface covered with a piece cut from a newspaper, and to lay the slate on a similar newspaper when showing the trick.
A neater method, and one which I should recommend for the present purpose, is to use a
"book" slate, with a loose slab, dropping from the one side into the other when the slate is closed, after the fashion of the card-box described at p. 102. With a little care in manufacture, such a slate may be so adjusted that it can be handed round among the audience after the disclosure of the figures. To that end, each of the inner edges of the frame on each side is slightly chamfered, but not to quite the same extent. In the one side (that on which the word or number to be produced is written) the moveable slab should fit quite loosely. In the opposite side, on the other hand, it should, when pressed home, fit tightly; so much so, that to get it out again, it must be prised out with the point of a table-knife.
The working of the trick will now be pretty obvious. The total (in this case, 1585) is written on what I may call the more open side of the slate, and the moveable slab inserted over it.
The performer cleans the visible surfaces. He then closes the "book" in such manner that the side which held the loose slab shall be uppermost, and lays it on the table or floor. When he again picks it up, and opens it, the loose slab has fallen into the opposite side, and the writing is exposed. A quick downward pressure with the thumbs forces the loose slab home in its new quarters, when the slate may be passed round for inspection, without any fear of its telling tales.
My own method of working the slate trick in a case of this kind is a good deal more audacious, but by no means difficult, if the performer's nerve is to be relied on. I have a sort of tailor's thimble (my own is of boxwood, but metal or celluloid would probably be the better material), in the front portion of which (i.e. that covering the ball of the thumb) a little piece of French chalk is set, like the stone of a ring. This rests, till needed, mouth upwards, in the right vest-pocket, pushed well up against the inner corner, in which position it can be instantly secured by dipping the tip of the thumb into the pocket. By then slightly bending the thumb, it is brought inside the hand, and out of sight.
The trick is in this case worked with an ordinary school slate, of small size. After cleaning this on both sides with a damp cloth, I take it upright in the left hand, and show one side to the company; then transfer it to the opposite hand, which has meanwhile secured the
"thimble," and show the opposite side in like manner. While the slate is thus held, in an upright position, by the fingers of the right hand, the thumb writes the desired figures on the hinder side;
the French chalk making no sound. The slate is then thrown down with this side downwards.
When it is in due course picked up again, the writing is revealed.
Whichever method of working be adopted, the performer will do well to take back the three "faked" cards from the Grand Panjandrum at the first opportunity, as, if they got into wrong hands, it might be discovered that the numbers on them were not those actually written by the spectators.