Contains approximately 250 formulas on 220 written pages; the rest of the pages are blank. Appears to be a compiled book, with formulas copied or written at around the same time, handwriting and ink density is uniform throughout the formula section. Includes an alphabetical index at the front. Formulas appear circa 1905-1910. Clipping dated 1905 pasted in at back. Pages 474-478 contain financial summary in format found in previous books, dated from January 1908-July 1912.

Notebook contains approximately 60 drug formulae; likely a compiled book.

Contains approximately 141 formulas. Many formulas also accompanied by advertising materials or printed labels for various T. Eaton proprietary medicines, many attributed to Lewis (for example, no. 35, "Lewis' Liquid Antiseptic), pasted in on some pages. Formulas are numbered 1-141 (instead of page numbering). Appears to be one part of a larger reference notebook set of Lewis's work.