"The present edition of The Seaman's Medical Friend is a new book rather than a mere revision of an old one; since the whole of that portion which relates to the Preservation of health, and the symptoms and treatment of diseases and injuries, has been entirely rewritten. The part on medicines, their doses, &c., has been printed but with a few alterations from the former edition. In the description of the nature and cure of Diseases and Accidents, I have avoided, as far as possible, the use of technical terms, and I believe, therefore, that the whole will be found intelligible to all its readers.
"It will be obvious that a complete treatise on all diseases is not demanded here, but simply an account of those likely to arise among sailors; with directions for such treatment as the remedies and assistance at hand render possible—and it is hoped that in this respect the present work will be found to justify its name of The Seaman's Medical Friend" (Preface). Digital facsimile of the 1857 second edition from Google Books at this link.
When I created this entry in February 2017 no record of the first edition was available in OCLC.