Enquire within upon everything

vii. If the trump-card be not taken into the dealer's hand at the expiration of the first round, it may be treated as an exposed card, and called. [After this, no one has a right to ask what was the trump-card, but he may ask "What are Trumps?"] viii. If the third hand play before the second, the fourth has a right to play before his partner; or if the fourth hand play before the second or third, the cards so played must stand, and the second be compelled to win the trick if he can. ix. If a player lead out of his turn, or otherwise expose a card, that card may be called, if the playing of it does not cause a revoke. [Calling a card is the insisting of its being played when the suit comes round, or when it may be played.] x. If a player trump by mistake, he may recall his card, and play to the suit, if the card be not covered; but he may be compelled to play the highest or lowest of the suit led, and to play the exposed trump when it is called by his adversaries. xi. If, before a trick be turned, a player discover that he has not followed suit, he may recall his card; but the card played in error can be called when the suit is played. xii. Before a trick is turned, the player who made it may see the preceding trick. [Only one trick is to be shown; not more, as is sometimes erroneously believed.]