E-text prepared by Robert Shimmin, Linda Cantoni, and the Project Gutenberg Online Distributed Proofreading Team (http://www.pgdp.net). Color title-page images were generously provided by the University of Pennsylvania Schoenberg Center for Electronic Text & Image (http://dewey.library.upenn.edu/sceti). Transcriber's Notes: This e-book was prepared from a facsimile of the 1661 first edition and contains spelling, capitalization, and punctuation inconsistencies typical of the era. These have been preserved as they appear in the original. Printer errors have also been preserved. Those mentioned in the Errata at the end of the book are noted with [Errata: corrected text]. Other obvious printer errors are noted with [Transcriber's Note: corrected text] where the meaning might be unclear without the correction. See also the printer's note preceding the Errata, which contains material omitted from the text (the place where it should be inserted is marked in the text with a Transcriber's Note). There are a number of sidenotes in this book, most of which function as footnotes (e.g., citations to other works) and some of which function as true sidenotes. For the sake of clarity, sidenotes functioning as footnotes have been converted to numbered footnotes, with number markers at appropriate places in the text. A character with a macron is represented by an equal sign. E.g., [=a] indicates "a" with macron. A table of contents has been provided for the reader's convenience. THE SCEPTICAL CHYMIST: OR CHYMICO-PHYSICAL Doubts & Paradoxes, Touching the SPAGYRIST'S PRINCIPLES Commonly call'd HYPOSTATICAL, As they are wont to be Propos'd and Defended by the Generality of ALCHYMISTS. Whereunto is praemis'd Part of another Discourse relating to the same Subject. BY The Honourable _ROBERT BOYLE_, Esq; _LONDON,_ Printed by _J. Cadwell_ for _J. Crooke_, and are to be Sold at the _Ship_ in St. _Paul's_ Church-Yard. _MDCLXI._ CONTENTS A Praeface Introductory Physiological Considerations The First Part The Second Part The Third Part The Fourth Part The Fifth Part The Sixth Part The Conclusion Printer's Note Errata A PRAEFACE INTRODUCTORY _To the following Treatise._