as follows. Should a 3 lie
exposed on the table, a player may place a 4 upon it, saying, "I build
a 7," and, if it is not disturbed before his next turn, he may then
take the two cards with another 7 from his hand. It follows that no
combination may be built unless the builder holds the proper card in
his hand. But a build may be increased. Thus, in the case cited above,
another player may put a 2 upon the two cards which make 7 and say, "I
build 9," in which case the original builder loses control of the
build unless he also holds a 9 in his hand or can himself increase the
build again; for instance, adding an ace and calling 10. In the old
way of playing the ace counted 1, the deuce 2, and so on as at whist,
excepting that all court cards counted 10. But in the popular
variation called _Royal Casino_, now almost universally played, the
ace counts either 1 or 14, the king 13, the queen 12 and the knave 11.
In this manner the opportunities for simple and increased building are
greatly multiplied, resulting in a much livelier game.

If a player has made a build he must take it in on his next play,
unless he can take some other card. He cannot have two builds on the
table at the same time, nor increase another build if he already has
one of his own. _Double Builds_ cannot be increased, e.g. if a player
combines a 3 and 4 lying on the table and places a 7 from his hand
upon them, saying, "I build sevens," this build can be taken only with
a 7, and cannot be built upon further. Of course in the case cited the
builder must still have another 7 in his hand. In playing partners
each may take in the other's builds, or may build to a card that has
been declared by his partner; e.g. if his partner has built an 8 that
has been captured by an opponent, he may build another 8 with a card
from his own hand to the 8 that he knows to be in his partner's hand,
even though he has no 8 himself. In _trailing_, i.e. laying down a
card without matching or building, one usually plays small cards,
avoiding aces and (if Big and Little Casino have not yet been played)
tens and deuces, as well as any cards one has reason to think will be
of service to the enemy. High cards are usually played last, as they
are stronger in taking combinations. Such rules are, however, quite
general, each situation calling for special treatment. In the last
round all cards remaining on the table be