To enjoy a comfortable travel via a simple and accurate operation by fitting universal joints at the branch points between the inboards and outboards of oars.

A universal joint 3 is fitted to each oar, clutches 6, 7 are installed at two positions on a boat, and the oar is operated through the clutches 6, 7. The operation of the oar is limited by the function of the universal joint 3 and the actions of two clutches 6, 7, i.e., the right and left of the universal joint 3 of the oar make the same motion concurrently, and no motion is allowed on one side only. When a handle 4 is moved, a blade 5 makes the same motion concurrently, and the oar can be operated. The primary performance of the boat traveling in the forward direction of a rower which has been the desire of fanciers for a long period can be exerted.