Hamburger Chain

William E. Singer, 87, founder of the Royal Castle hamburger chain who opened the first of his nickel hamburger restaurants in 1938 in Miami with a $1,000 investment. By the 1960s, the restaurants had become the third-largest short-order chain in the country. When the chain was sold in 1969, there were 175 Royal Castles in Florida, Georgia and Louisiana. The burgers were thin and about two half-dollars wide and were served often with birch beer, which came in tall, frosty mugs.

Burger King Corp., the nation's No. 2 hamburger chain hit recently by sagging sales, said today it had selected N. W. Ayer Inc. for its $200-million domestic advertising account, severing an 11-year association with J. Walter Thompson USA. It was the biggest single account change ever, industry analysts said. Ayer, Thompson and D'Arcy Masius Benton & Bowles had been identified last month as being finalists for the account.