He quickly glides his heel along the iron; but the lower-class Arabs, who all walk with naked feet, have the lower part of the foot as hard as a horse’s hoof, hence, this horny part burns without occasioning the slightest pain. And, besides, may not chance have taught the Aïssaoua certain precautions known to more than one European juggler, before Dr. Sementrici proved their use and explained them to the public? Let us quote some performances of our own mountebanks, and we shall find that the followers of the Aïssa as miracle-mongers are a long way behindhand in their pretended marvels. In February, 1677, an Englishman, of the name of Richardson, came to Paris, and gave some very curious performances, which proved, according to his statement, his incombustibility. He was seen to roast a piece of meat on his tongue, light a piece of charcoal in his mouth by means of a pair of bellows, seize a bar of red-hot iron in his hand, or hold it between his teeth. This Englishman’s servant published his master’s secret, which may be found in the _Journal des Sciences_.[G] In 1809, a Spaniard, of the name of Leonetto, gave performances at Paris. He also handled a bar of red-hot iron with impunity, passed it through his hair, or stepped upon it; drank boiling oil, plunged his fingers into melted lead, put some on his tongue, and ended his performance by licking a piece of red-hot iron. This extraordinary man attracted the attention of Professor Sementrici, who began carefully watching him. The professor remarked that the tongue of the _incombustible_ was covered with a grey layer, and this discovery led him to try some experiments on himself. He discovered that rubbing in a solution of alum, evaporated to a spongy state, rendered the skin insensible to the action of red-hot iron. He also rubbed himself with soap, and found that even the hair did not burn when in that state. Satisfied with these investigations, the physician rubbed his tongue with soap and a solution of alum, and the red-hot iron produced no sensation on him. The tongue, when thus prepared, could also receive boiling oil, which grew cold, and could then be swallowed. M. Sementrici also detected that the melted lead Leonetto employed was only Arcet’s metal, fusible at the temperature of boiling water. (For further details consult the historic notice of M. Julia de Fontenelle, in Roret’s _Manuel des Sorciers_, page 181.) These explanations may appear sufficient to disprove the pretended incombustibility of the Aïssaoua; still, I will add a personal fact, whence the conclusion can be drawn that a man need not be inspired by Allah or Aïssa to play with red-hot metals. Reading one day the _Comus_, a scientific review, I found a critique of a work called _Study on Bodies in a Spheroidal Shape_, by M. Boutigny (d’Evreux). The editor of the review, the Abbé Moigno, quotes several of the most interesting passages, among them being the following: