Steps:1. Clamp the broken pieces to a workbench and cut away any remaining bits of dowels that stick above the surface. Use a pull saw to trip the dowels flat, then take a file and file down the surface until it's nice and level (figure A).
2. Use a combination square to measure the diameter of the dowels (figure B).
3. Select the same size drill bit for drilling out he dowels. Punch a dimple in the center of each dowel with an awl to make starting the drill easier.
4. Mark your drill bit with a piece of tape so you drill half the length of the dowel (figure C).
5. Smear half of a new dowel with wood glue and drop it into the hole. Tap it lightly into place with a hammer (figure D).
6. Repeat the process until you've added dowels to the ends of all the legs.
7. Finally, drill the old dowels out of the joints on the tables where the legs attach. Fill the holes with a liberal amount of glue and attach the legs.