–Shots were exchanged between the U. S. Steamers Freeborn and Monticello, and a rebel battery at Sewell’s Point north of Elizabeth River, Virginia.–(Doc. 177.) –Two schooners with secession troops on board were taken by U. S. steamer Freeborn, in the Potomac, 10 miles below Fort Washington.–N. Y. World, May 21. –The rebels at Harper’s Ferry, [...]