For a while last week, the most important instrument of Government was the thermometer that measured the ups and downs of presidential temperature. Even as the nation's most celebrated backache seemed on the mend, John Fitzgerald Kennedy came down with what the White House physician, Dr. Janet Travell, described as a "mixed bacterial and viral infection."
Until the virus came along, the President's month-old lumbosacral strain was, by official accounts, coming along fine. After a couple of days of rest at Middleburg, the President hopped about on his crutches with decreasing evidence of...