The amazing thing about this card trick is that you won't be able to touch the cards, because they will be inside the glass the whole time. Placing the pack, face out in the glass, the magician states that he's going to find all four aces using special card. He reaches into the glass and pulls out a red number card (we will use the Ten of Hearts for the example ) and puts it in front of the rest of the cards in the deck so that the ten of hearts is the card the spectator now sees looking at them through the glass. The magician then states that the red 10 will find an ace. Holding the glass by the stem, the magician passes a cloth over the glass, quickly. The red 10 has been replaced by a red ace! The magician then takes the red ace and puts it in back of the deck and passes the cloth again. This time, the red 10 is replaced by the other red ace! Another pass, and there is a black ace! The magician takes the ace and puts it in back of the deck. Another pass, and there's the last black ace! Now pull out the pack and put it back in the case. All of this magic occurs in the glass, so there's apparently no way that you could've manipulated the cards!