Cardinal Books, a small Maitland, Fla., publisher of nonfiction books, has abandoned its efforts to develop an e-book program. The company had been acquiring electronic rights from small publishers and planned to sell e-book editions through its Web site, But according to Cardinal CEO Maxx Robinson, the company "has been bleeding cash" and has lost an estimated $1.5 million on its e-book program over the last three years. As a result, Cardinal has eliminated two digital production positions and will shut down by June 1.