Life and works of Agathodaemom
Agathodaemon was an alchemist in late Roman Egypt, known only from fragments quoted in medieval alchemical treatises, chiefly the Anepigraphic, which refer to works of his believed to be from the 3rd century. He is primarily remembered for his various descriptions of elements and minerals, most particularly his descriptions of a method of producing silver, and of a substance he had created, which he called a 'fiery poison', and which, judging by his account, was arsenic trioxide, a highly toxic amphoteric oxide. He described the 'fiery poison' as being formed when a certain mineral that was believed to be realgar or orpiment was fused with natron that occurs in sodium carbonate, and that dissolved in water to give a clear solution. He also wrote of how, when he placed a fragment of copper into the solution, the copper turned a deep green hue, lending further validity to the suggestion that orpiment or realgar was used, as they are both arsenic ores, and this would be the hue achieved from the copper after it had been placed in the arsenic trioxide had the substance formed been copper arsenate.
Agathodaemons discoveries exist as part of the foundations for later use of poison, as arsenic and related substances were used regularly in later centuries as means of poisoning and murder. Since the only records of his existence are references in later works, he may be apocryphal, but since the practice of alchemy itself began to decline around the time he is believed to have lived, and it may be that much of his writing was lost. Some of the writings of other alchemists on alchemy of the time were preserved and saved.