Laurens Catelan, Master Apothecary of Montpellier, and Apothecary in Ordinary to Monseigneur the Prince de Condé, has left a full report of his discourse on the occasion of his dispensing a batch of Theriaca at Montpellier on September 23, 1628. It is a most interesting lecture, full of curious old facts chiefly about poisonings, and inspired with an unshakable faith in the importance of the operation in which he was engaged. The exordium is explanatory of the ceremony: “The regulations and statutes under which we live in this city,” says Master Catelan, “require that whenever we prepare either Theriaca, Mithridatium, Confection of Hyacinth, or Confection Alkermes, the compounding shall be done in public, and in the presence of the very illustrious professors of this famous University of Medicine, so that they may have the opportunity of censuring or approving the ingredients, and the public may therefore be assured of the fidelity of these important medicines. “This is why I have here spread out before you all these drugs which are used in the composition of the great and famous Theriaca. “But as I am honoured with the attendance of such an august assembly, I ought not, I think, to omit to lay before you some of the singularities associated with the history and composition of this remedy, and I will divide what I have to say on these subjects into three sections, namely-- “(1) The discoverer of this compound; (2) the purpose of the invention; and (3) the reasons why these drugs and no others of the multitude known to us have been chosen for this purpose.” The lecturer then entered upon a history of Mithridates and his wonderful immunity against poisons; of his defeat by Pompey, of the recovery of his formula, of the additions made to it a hundred years later by Andromachus, and of the preservation of directions for making it which Galen wrote some fifty years after Andromachus had completed his invention. At this point the book tells us there was an interval, and some music was performed. When the lecturer resumed he proceeded to tell of the risks which princes and nobles ran of being poisoned in those old times, and of the precautions taken against such crimes. Of the rings and amulets they wore, of the tasters they employed, and of the treatment such as Mithridates went through of accustoming his system to poisons to such an extent that they took no effect on him. He quotes in support of the belief in this method of ensuring immunity against poisons two or three stories from the classics which one would have thought would have been too strong even for a professional eulogist of Theriaca.