This one from 1934 is marked:
1223 3/4 PLVMB LA 4 D
Both plomb bobs point down, of course. It is just a tad over 8" long.
I compared it with a more common combination wrench which is stamped:
1224 . PLOMB MADE IN U.S.A. . 3/4
Again, the plomb bobs point down, but this wrench is a full 9" long.
I am familiar with the earlier wrenches marked Los Angeles, but were the earlier wrenches shorter?