at the trial concerned a ring displayed two snakes, one of gold and one of platinum, biting one another's tails, similar to what Kekulé would dream of later.

Following four years of study in Giessen and a brief compulsory military service, he took temporary assistantships in Paris (1851-52), in Chur, Switzerland (1852-53), and in London (1853-55), where he was decisively influenced by Alexander Williamson. His Giessen