Dovetail

Shuffle "Swallowtail" creates the appearance of shuffling cards, but in fact the cards in the deck lie in the order in which they lay before shuffling. The method of execution is as follows. During the shuffling of cards, the sharpshooter divides the deck into two parts and passes one half of the deck through the other, with the arrangement of the two parts of the deck as in the figure below.

Then the shuler covers the cards with his right hand, skipping half of one deck, half the other deck, and from the latter describes the movement in a semicircle to the right, with this turn it separates from the rest of the deck and the sharper has the opportunity to put it again under the first half of the deck, As she lay before the shuffle.