N-Grams & Culturomics
Our current Giffords Lecturer (Prof. Peter Harrison, Oxford University) introduced us to Google N-Grams, which enables one to track the comparative frequency of a word or phrase in various corpora of books across time. It’s a lot of fun to play with, and with the right kind of care in constructing a search can yield some useful results.
Here’s the URL: http://ngrams.googlelabs.com/info
And from that site there are links to further explanations and advice about how to use the “ngrams” facility more intelligently.