"Filer la carte" is to change one card for another.

In the hands of an adroit sharper, this change is performed so instantaneously, that it is almost impossible for the quickest eye to detect it.

Let us suppose that, in dealing the cards, the Greek discovers, by means which I will hereafter explain, that the card he is going to give to his adversary would be advantageous to himself, he hides, or slips away, the card which ought to have been dealt to his adversary, and gives him, instead, the one which follows.

I will just explain how this manoeuvre is managed.

When the Greek intends to perform this trick, he takes care, whilst dealing, to push two cards a little in advance of the rest of the pack, as shown in Nos. 1 and 2 in figure 10.

In a regular deal, No. 1 would be given before No. 2; but if the Greek thinks it to his interest to retain it, he substitutes the second for the first. Thus, by holding the two cards together, between his thumb and forefinger, he pushes them contrary ways, that is to say, he pushes No. 2 forward, and No. 1 backward, as represented in the figure below.

He then passes over the first card with his right hand, and gives the second. This feat, which I have been obliged to explain thus lengthily, to make it clearly understood, ought to be done instantaneously, and with the rapidity of lightning.

Those who are expert, whilst advancing the right hand to give a card, at the same time draw back the left. This manoeuvre completely deceives the eye, and may be practised as often as is necessary for the card in reserve to come into the hand of the Greek.

To give an idea how completely a person may be deceived by this trick, I will just relate what once happened to myself.

A certain Greek (of whom I have already spoken in my Memoirs) was anxious to show me this trick, and by way of illustrating his theory, selected the King of Spades, and placed it on the top of the pack. He then dealt the cards one after the other, and by thirty-one successive "filages," he so managed, that the King of Spades was the last card of the pack.

I acknowledge, and indeed I do so still, that so adroit was he, that though I knew the trick myself, I could not detect him.