Margaret Elaine McElroy and John Vincent Powell, who met en route to Europe for study, have become man and wife and will make their new home in Washington, D.C. The Rev. Ralph Powell, uncle of the bridegroom, officiated for the ceremony in Infant Jesus of Prague church, Flossmoor. The bride is the daughter of Mr. and Mrs. John L. McElroy, Jr., 18157 Stewart avenue, Homewood. A graduate of Illinois State university, she received a master’s degree from Georgetown university, Washington, D. C., and is a candidate for a PhD degree in French literature from Duke university. She has studied at the Sorbonne in Paris and at the Universities of Grenoble and Dijon. Powell, a recent graduate of Duke university law school, will begin a clerkship with Judge Paul McArdle of the Superior court of Washington, D.C. He has studied at Oxford university in England, the University of Fribourg and Dijon. Powell is the son of John Eris Powell, Chevy Chase, Md., and the late Ida Powell. A HOOD of off white silk jersey, matching the gown fabric, replaced the usual veil in the bride’s ensemble. The simple lines of the gown were broken only by a small, diamond-shaped ornament of seed pearls on the bodice. The bride carried white phalaenop sis orchids, white stephanotis and blue star-flowers. Miss Lynda Vieiram of Flossmoor was maid of honor. Bridesmaids were the bride’s three sisters: Mrs. Stephen Russ of Mundelein, Mrs. John McIntyre of Monmouth and Lorraine McElroy of Home wood. John Edward Powell, brother of the bridegroom, was a best man. Ushers were W. Page Montgomery of Durham, N.C.; John W. Malley, Jr., of Washington, D.C., and John L. Milanese of Bethesda, Md. A reception in Calumet Country club followed the ceremony. The young couple are honeymooning in Mexico before returning to Washington. Mrs. John Vincent Powell