  We define the category 2-Cob combinatorially and use this definition to prove
the existence of an orthogonal factorization system. In the second half of the
paper, we define oriented 1-Cob similarly and define a functor from oriented
1-Cob to 2-Cob. After defining this functor, the orthogonal factorization
system on 2-Cob is used, in turn, to prove the existence of an orthogonal
factorization system on oriented 1-Cob.
