Also see Thomas Farnaby. First published in 1633. L&M say the version Pepys bought in The Hague in 1660 was the 1648 edition.
“Index Rhetoricus” of Thomas Farnaby was a book which went through several editions. The first was published at London by R. Allot in 1633.
This text comes from a footnote on a diary entry in the 1893 edition edited by Henry B. Wheatley.
Index Rhetoricus et oratorius, By Thomas Farnaby, 1659
Chart showing the number of references in each month of the diary’s entries.