Take your hand away from the lower end and the paper will naturally remain in position. Then, holding the tube by the middle with the right hand, peel the paper away slowly from the bottom of the tube and put the paper between the lips for a moment while you take the top paper away. In doing this you make use of an excellent little piece of showmanship; you pretend to be very nervous.
The tube is now held perfectly still for a second or two, and as the audience know that it is full of water and cannot see that there is anything either at the top or bottom of the tube, the effect is very mysterious.
Put the paper which was on the top under the lower end, pressing it well round that end, and take the other piece from the lips and mould it firmly round the top. Then invert the chimney, thus bringing the disc with the hole in it to the top again. Again press the papers well round both ends of the chimney.
Remove the lower paper once more, and still the water remains in the chimney. At this point in the trick Mr. Devant had an excellent line of patter which I hope he will forgive me for giving away; it always brought a round of laughter. "Supported entirely by voluntary contributions."
Replace the paper on the lower end of the chimney, and pick up the hat pin. Place the pin in the top paper; of course, the pin passes through the little plug of soap in the glass disc. As you take the pin out again the air naturally gets in and the water begins to fall. (It will be understood, of course, that at this stage of the trick you hold the chimney over the bowl.) Directly you feel the water is moving put the pin back into its place; this is a very important "move."
The water rushes out, naturally taking the disc and paper at the lower end with it. The pin is sticking through the top paper and therefore through the top disc. Remove the pin, taking the disc and paper impaled on it, and push the paper off into the bowl; while you do this you can lift the first paper slightly out of the bowl, so that the top disc sinks to the bottom on the top of the one already there. Then remove both papers and hold up the bowl of water. All trace of the method you employed for bringing about this very mysterious effect is now concealed, for the glass discs cannot be seen at the bottom of the bowl. You pick up the pin and once more rattle it in the glass chimney to show that you have nothing inside it, and then you go on to the next trick.
I have heard conjurers say that if they get one good trick out of a book they have received excellent value for their money. If that be true—and I, for one, certainly think it is—then, thanks to Mr. Devant, purchasers of this book have no cause for complaint, for I know of no finer trick with water than "The Hydrostatic Tube."
One little helpful hint. When the conjurer is about to put the pin through the top paper he may have a slight difficulty in finding the exact place for it. A little stain on the plug of soap will help him to find the right place at once.
The trick needs a steady hand, and the conjurer must not know the meaning of "nerves," but if he will see that the discs fit the ends of the glass chimney perfectly and will carry out these directions he need have no fear of any mishap.