Heat, the cause of many wonders--Its universal diffusion and application--Story of a burning-glass--The Augustine friars and the Jesuits--Impostures as to the endurance of heat--Burning mirrors--The blow-pipe--The Giants’ Causeway--Application of currents of heated air--Travelling by steam. Heat is everywhere present: every body that exists contains it in quantity to which we can assign no limits. The endless variety of forms which are spread over and beautify the surface of the globe, are to be traced to its influence. Without it, the land and the water would fall into one formless and impenetrable mass, and the air now essential to life, prove absolutely poisonous. We shall find in connexion with it, therefore, many extraordinary phenomena. When Labat the Jesuit visited the Peruvians, he took the naked arm of one of them, and, concentrating on it the rays of the sun by means of a powerful lens, soon made him cry out with pain, while the others looked on with wonder, not unmixed with indignation. How could this effect be produced? was instantly the question; and, as promptly, the cause was declared to be infernal. In vain did Labat assert that it was merely natural. The Peruvians made many attempts to obtain possession of the lens in order to destroy it, and deliver themselves from the power of that which they regarded as able to bring upon them the vengeance of the gods. Much surprise has sometimes been awakened by an apparent insensibility to intense heat. An instance of this occurred when a rivalry existed between the Augustine friars and the Jesuits. The father-general of the Augustine friars was dining with the Jesuits; and, when the table was removed, he entered into a formal discourse of the superiority of the monastic order, and charged the Jesuits with assuming the title of “_fratres_,” while they held not the three vows which other monks were obliged to consider sacred and binding. The general of the Augustine friars was very eloquent and very authoritative--and the superior of the Jesuits was very unlearned. The Jesuit avoided entering the lists of controversy with the Augustine friar, but arrested his triumph by asking him if he would see one of his friars, who pretended to be nothing more than a Jesuit, and one of the Augustine friars who religiously performed the three vows, show instantly which of them would be readier to obey his superior?