When you are searching for a word that is more precise than another though similar in meaning, you don't browse Piozzi's. Yet British Synonymy, the first English book of synonyms, was written by Hester Lynch Piozzi. Nor do you grab your Girard's. Published 76 years before Piozzi, the 1718 book of French words appears to be the first collection of synonyms in any language. What you reach for is your Roget's. Originally published in 1852, having been compiled over the course of more than four decades by the eponymous but strangely anonymous Peter Mark Roget, the thesaurus we know and love was not the first of its kind... Slate.
Also at Slate, a brief look at overwhelming anxiety.