The book "Medical research and observations, volume 1. Second edition, revised and expanded by the author" is an edition that belongs to the classics of medical literature. The author of this work is the famous American doctor Benjamin Rush. In this book, he explores and analyzes a variety of medical issues that he has worked on throughout his life. "Medical Research and Observation" is a valuable source of knowledge for medical professionals and anyone interested in the history and development of medicine. The text of this book has been revised and expanded by the author to make it even more interesting and useful for readers.