A labeling scheme for the gaps of the bridges of a broken cycle C′ of a biconnected graph G is developed. This labeling scheme incorporates the ideas of lexicographic order and of attachment order and is used to order the set of gaps (both proper gaps and cospan gaps) of all bridges of the broken cycle C′. Thus a linear order relation is induced on the set of gaps. An O (¦V¦+ ¦E¦) algorithm for the construction of spanning forests for the bridge graph, G c′ , of the biconnected graph G = ( V, E) with respect to the broken cycle C′ is given. As a bonus, this algorithm yields a set of instructions to produce a planar embedding of a biconnected graph, should one exist.