Down comes a deluge of sonorous hail, Or prone-descending rain. Wide-rent, the clouds Pour a whole flood, and yet, its flame unquenched, Th'unconquerable lightning struggles through. Ragged and fierce, or in red whirling balls, And fires the mountains with redoubled rage. Black from the stroke, above, the smould'ring pine Stands a sad shattered trunk; and, stretched below, A lifeless group the blasted cattle lie. James Thompson, The Seasons (1727) have been investigating ball lightning for more than two decades. I published a ball lightning report in Nature in 1976 that received worldwide publicity and I consequently many people wrote to me with accounts of their own experiences. Within a very short time, I had accumulated about 200 firsthand accounts, and the file has continued to grow steadily since then. Several things impressed me. Few of those who wrote to me had any detailed foreknowledge of ball lightning at the time of their observation. Nonetheless, once reports of other phenomena such as St. Elmo's fire had been eliminated, the remaining descriptions were remarkably consistent. Furthermore, nearly all who contacted me were keen to have an explanation of what they had seen and seemed entirely sincere.