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.

Budget report for 1929/31 deals also with the operations of the fiscal year ended June 30, 1928 and the estimates for the fiscal year ending June 30, 1929.

One of the mathematical challenges of modern physics lies in the development of new tools to efficiently describe different branches of physics within one mathematical framework. This text introduces precisely such a broad mathematical model, one that gives a clear geometric expression of the symmetry of physical laws and is entirely determined by that symmetry.The first three chapters discuss the occurrence of bounded symmetric domains (BSDs) or homogeneous balls and their algebraic structure in physics. The book further provides a discussion of how to obtain a triple algebraic structure associated to an arbitrary BSD; the relation between the geometry of the domain and the algebraic structure is explored as well. The last chapter contains a classification of BSDs revealing the connection between the classical and the exceptional domains.With its unifying approach to mathematics and physics, this work will be useful for researchers and graduate students interested in the many physical applications of bounded symmetric domains. It will also benefit a wider audience of mathematicians, physicists, and graduate students working in relativity, geometry, and Lie theory.