Roosa, David Bennet St. John. A Vest-Pocket Medical Lexicon. Being a Dictionary of the Words, Terms, and Symbols of Medical Science. Collated from the Best Authorities, with the Addition of New Words Not Before Introduced into a Lexicon. With an Appendix. By D. B. St. John Roosa, M.D., Aural Surgeon to the New York Eye and Ear Infirmary. New York: Wm. Wood & Co., 61 Walker St., 1865. First edition. [iii; 5 – 268 pages]. 8 cm. Brown leather wallet-style binding, with “Wood’s Medical Lexicon” on the spine in gilt lettering. Page edges gilded. An appendix of terminations taken from Hay’s edition of Hoblyn’s Medical Dictionary follows p. 244. “The Abbreviations and Symbols Used in Prescription Writing” follows on p. 250 -257. On p. 257 begins “Examples of Prescriptions” to p. 259. “Poisons and Their Antidotes” begins on p. 260 to p. 263. “A Table of Elemental Substances with Their Symbols and Equivalents” follows on p. 264 – 266. An “Advertisement” for Diseases of the Ear by Anton Von Tröltsch of the University in Wurzburg, Bavaria, on p. 267-268 by William Wood & Co., Publishers, 61 Walker Street, New York. Ownership signature of A. P. Davis, Jackson, Maine in pencil and penmanship practice. Back cover reinforced. Printed on sturdy paper. Worn from use but still a usable small book in good condition. Page 257 -258 has a ragged top edge with no text loss. Bottom stitch missing, others present and holding. Two printed book copies (1865) were located.