69. Dummy being blind and deaf, his partner is not liable to any penalty for an error whence he can gain no advantage. Thus, he may expose some, or all of his cards, without incurring any penalty.
Exposed Cards.
70. If after the deal has been completed, and before the trump declaration has been made, either the dealer or his partner expose a card from his hand, the eldest hand may claim a new deal.
71. If after the deal has been completed, and before a card is led, any player shall expose a card, his partner shall forfeit any right to double or re-double which he would otherwise have been entitled to exercise; and in the case of a card being so exposed by the leader's partner, the dealer may, instead of calling the card,
require the leader not to lead the suit of the exposed card.
Cards liable to be Called.
72. All cards exposed by the dealer's adversaries are liable to be called, and must be left face upwards on the table; but a card is not an exposed card when dropped on the floor, or elsewhere below the table.
73. The following are exposed cards:—
I. Two or more cards played at once.
II. Any card dropped with its face upwards, or in any way exposed on or above the table, even though snatched up so quickly that no one can name it.
74. If either of the dealer's adversaries play to an imperfect trick the best card on the table, or lead one which is a winning card as against the dealer and his partner, and then lead again, without waiting for his partner to play, or play several such winning cards, one after the other, without waiting for his partner to play, the latter may be called on to win, if he can, the first or any other of those tricks, and the other cards thus improperly played are exposed cards.