In this special episode of “Post Reports,” columnist Petula Dvorak reads her first installment of The Post’s revealing history column, Retropolis. James Buchanan barely won the presidency. The nation was roiling in the debate over slavery. So when Buchanan became gravely ill before his inaugural address, it wasn’t a stretch to suspect an assassination attempt. The presidential entourage all stayed at the posh National Hotel on Capitol Hill and they fell ill, too. It hit more than 400 guests of the hotel and more than 30 died. It became known as the mysterious National Hotel Disease and confounded Washington for months. This column details the story of the sickness and the doctors and detectives who searched for the cause.The piece was reported, written and read by Petula Dvorak. Audio production and original music by Bishop Sand.