In that case, it may be that the stopper which the Declarer
thinks he has in the suit can be captured, and the lead, therefore,
should be a low card.

NUMBER-SHOWING LEADS

The lead in Auction is materially simplified by the fact that
number-showing is not nearly so important as in Whist, and really only
becomes of value when opening a small card against a No-trump
declaration. In that case the lowest should always be led with four in
the suit, because the partner, having the Dummy spread before him,
being able to count his own hand, and being informed by the lead
regarding the leader's length in the suit, can generally tell the exact
number held by the Declarer, and can, therefore, accurately determine
whether it is better to continue that suit or try some other. It
happens more frequently than would be supposed that when a four-card
suit is opened with a small card, the Dummy and Third Hand have only
four cards of it between them. The Third Hand can then, if the leader
have shown exactly four, mark it as the long suit of the Declarer, and
make an advantageous shift. This is the only method of giving this
warning. If the fourth-best lead be not adopted, the suit must, in most
cases, necessarily be continued to the great benefit of the Declarer.

Number-showing by the lead of a small card (one of the rudiments of
Whist) is doubtless thoroughly understood by most Auction players; it
consists in leading the fourth best, when the suit is not of such a
character as to demand a high card or intermediate sequence opening.
This informs the partner that the leader has exactly three cards in
that suit higher than the card led, and that he may or may not have any
smaller card.

For example: the leader has Queen, 7, 6, and 4; the Dummy, a singleton
(the 3); and the Third Hand, who wins the trick with the Ace, only two
others (the 8 and 2). The Third Hand can place the Declarer with five,
as the leader, having opened his lowest, can have had only four
originally.

Number-showing leads in high cards, so advantageous in Whist, are
absolutely unimportant in Auction, and only complicate the situation.
They are not given in the table of leads appended at the end of this
chapter, nor is their use permissible, even by the Whist-player of the
old school who is thoroughly familiar with their meaning. He must
realize that Auction is not a number-showing game, and must be content
to limit his skill in that respect to the fourth best,