New Experiments Physico-Mechanical, Touching the Air. Whereunto is added A Defence of the Author's Explication of the Experiments, Against the Objections of Franciscus Linus and, Thomas Hobbs. Some Considerations Touching the Usefulnesse of Experimental Philosophy. Propos'd in a Familiar Discourse to a Friend, by way of Invitation to the Study of It. Parts I & II by Robert Boyle - 1682

London : Miles Flesher for Richard Davis, bookseller in Oxford, 1682 The 3rd edition of Boyle's work on Air (first published 1660) in 3 parts, bound with the 2nd edition, published in 1664, of the first part of his work on the usefulness of Experimental Natural Philosophy (first published in June 1663), and, probably, the first edition of the second part of Natural Philosophy published in 1671. In contemporary vellum binding - with some marking and cracking at the joints, and a small repair at the bottom of the spine. 'New Experiments' was a landmark work enabled by Torricelli's development of the mercury barometer.This allowed Boyle to carry out his series of experiments based on reducing air pressure; using the barometer to provide objective measurements. Experiment 43 is particularly significant: Boyle placed warm water in a vessel and then reduced the air pressure and observed the outcome. The water started to 'boil', thus demonstrating that the liquid/air interface is affected by pressure as well as temperature. It is now known that even cold water can transition in to water vapour if the atmospheric pressure is lowered enough to allow the water molecule to escape from the liquid phase. Boyle's Spring and Weight of Air, published in 1682, set out his defence against strong criticism from Franciscus Linus who refused to accept the existence of a vacuum. The third book is An Examination of Mr 'Hobbs' Dialogus Physicus. Hobbes criticised Boyle's experiments, claiming that 'subtle air' had entered his apparatus either via the stop cock, or by permeating through the glass itself. It seems an odd claim, but Hobbes was a very argumentative man. Considerations Touching the Usefulness of Experimental Natural Philosophy, is an extensive treatise on the value of experimentation - using observation and analysis of phenomena to put forward theories. Contents: front endpaper with pencil annotation; title page; title page for New Experiments 1682; to the Reader 6pp; 'Friendly Reader' 2pp; Summary 4pp (double column); Text 203pp; title page A Defence..1682; Publisher to the Reader 2pp; The Author's Preface & declarations 8pp; text pp 1-89 with 1 plate; the Explication of Refraction pp 90-103; citations englished pp 105-112; summary p113-117; blank; title page 'An examen...' 1682; Preface 6pp; text pp 1-88; citations englished pp 89-99; fragment of second plate; summary of contents pp 100-102; Catalogue of author's works 2pp; title page 'Some Considerations...' 1664; publisher to the reader 8pp; author's advertisement 4pp; half title 1st part; essays pp 1-116; citations englished p 117-126; index 4pp; half title 2nd part; text pp 1-299 [there are pagination errors: 183 to 193, 288-287 and p105 is missing the tip of the bottom corner with no loss of text]; half title - apppendix; text pp 303-404 with diagram in text at p 313; [pagination error 376-387]; citations englished pp 405-416; landscape printed page; index of 2nd part 15pp; finis; note to reader on pagination 1p; later ink in memoriam note on rear end paper. The text is generally clean and in good to very good condition with the odd mark. There is brown toning to the edge of pages. Of the 2 plates, plate 1 has extensive browning and most of plate 2 is missing. There is a little worming to the bottom margin of some pages in the final appendix section - not affecting text. Please enquire if you would like to see further images of this work.