New experiments physico-mechanical, touching the air

A Summary of the Contents of the several Chapters.

CHAP. I.

THe occasion and scope of the present Treatise. Reasons why Mr. Hobbs might have employed himself otherwise, and have spared this Dis∣course, p. 2. Why the Author would have been contented he had done so, ibid. Why he now undertakes the Reply, p. 3.

CHAP. II.

Of some mistakes of Mr. Hobbs touching matters of Fact and the Authors Doctrine. That he mistakes in ascribing the Explications and Experiments in the Physico-Mechanical Treatise of the Society at Gresham College, p. 3. the Experiments having been seen done long, and the book published, before the Society began, &c. p. 4. That the Experiments were not devised nor employed to prove a Vacuum, Ibid. Whether Mr. Hobbs by the Experi∣ment of the Gardeners Watering-pot demonstrates that there can be no Vacuum, p. 5. That if the Watering-pot were tall enough, the water would run out with unstopping the upper Orifice, prov'd by M. Paschal's Experi∣ment, p. 6. The way of Argument on both sides compared, p. 7, 8. Why the Author did not assign the cause of Springs, p. 9. That Mr. Hobbs his account of Springs is imperfect, and that he has not solved the Phaenomena of them, p. 10, 11, 12, 13. That he mistook the Authors notion of the Air, p. 14. 15.

CHAP. III.

Wherein the Weight and Spring of the Air are asserted against Mr. Hobbs. Several Experiments recited that prove the real Weight of the Air, p. 16, 17. Mr. Hobbs's Objections against the Experiment of the heaviness of a blown Bladder, p. 17, 18. answered, p. 19. The Spring of the Air asserted from Mr. Hobbs's concessions, p. 20, 21, The same asserted by particular Experiments, p. 22, 23. Mr. Hobbs his answer to that of the Bladder considered, p. 23, 24. Experiments of the Spring of the Air not comprest, p. 25.

CHAP. IV.

Wherein Mr. Hobbs his principal Explications of the Authors Phaeno∣mena are examined. What things Mr. Hobbs takes for granted, p. 26. His Hypothesis considered of the simple circular motion, whether it be not precariously ascribed to aqueous and earthy Particles, p. 27, 28. Whether in

the exhaustion of the Cylinder any Vacuum be produced, p. 29, 30, 31. Experiments to prove that the Glass is in great part devoid of common Air, p. 31, 32. Whether a purer sort of Air may unperceived dive under Water to pass into the Receiver betwixt the Cylinder and the Suker, p. 33, 34. That the Cartesian way of explicating this Phaenomenon in favour of the Plenists is more plausible than Mr. Hobbs's, p. 35. Whether the place de∣serted by the suspended Mercury in the Torricellian Experiment be empty or full of Air, p. 37, 38. Mr. Hobbs's Explication of that Experiment of Mr. Boyle, in which the Air impells up the Sucker together with above 100. pound weight, p. 39, 40. The Examination of this Explication, p. 41, 42.

CHAP. V.

In which divers scatter'd Explications and other passages in Mr. Hobbs's Dialogue are examined: His Explications why water without visible force ascends in a slender Pipe considered, p. 44, 45. Why the stopple of the Cover of the exhausted Receiver so much gravitates, considered, p. 46. His Explication and the Authors, why in the exhausting of the Receiver water let down into it boyles as it were or bubbles there, viewed and compared, p. 47, 48 Whether the Phaenomenon of this water bubbling in the Receiver be an evidence that there is no vacuity in the Receiver, p. 49, 50. Whether Animals in the exhausted Receiver dye for want of Air, or for the causes assigned by Mr. Hobbs, p. 51, 52. That the Author asserts not the proof of a Vacuum or Plenum to depend on the Hypothesis of the Spring of the Air, p. 53. That the Air in the exhausted Receiver is not thicker but thinner, not heavier but lighter, proved by Experiments, p. 54 55. The Epicurean Hypothesis of fire, and the effects of the Sun-beams through Burning∣glasses, p. 57. Whether he deserves a censure that calls kindled coals fire, p. 58.

CHAP. VI.

Wherein other passages of Mr. Hobbs's Dialogue that concern the Author are examined. That the Experiments of the Needle's motion in the exhausted Receiver, and of sounds being audible, and objects visible there, are recon∣cilable to the doctrine of the Atomists, p. 59. Whether from the cohesion of two Marbles the non: existence of a Vacuum follows, p. 60, 61. How the lower Marble is upheld, p. 62, 63. The power of the oblique pressure of the Air to these effects illustrated by Experiments, p. 64. Whether the throwing up of water in the Glass fountains, invented by Vincenzo Vincenti of Urbin, can be explicated by the Spring of the Air, p. 67, 68. Mr Hobbs's Explication of the cause of waters being suspended in a Gardeners Watering∣pot examin'd, p. 69. An Experiment purposely devised to shew that both

Vacuists and Plenists should admit an Elastical power in the Air, p. 70, 71. Mr. Hobbs's correction of the Authors discourse about the ascension of water in Siphons and Filtres animadverted, p. 72. Some unhandsom passages, and such as shew the unequal estimation Mr. Hobbs has of his own and others preformances in Philosophy, p. 73, 74. What parts of Mr. Hobbs's Treatise, and why, past by without censure by the Author, p. 75.

CHAP. VII. (Being an Appendix to the past Discourse)

Wherein is examined what Mr. Hobbs teaches concerning Fluidity and Firmness. Mr. Hobbs mistakes, and so misreports, the Authors Doctrine of the cause of Fluidity, p. 77. His Animadversions on the Doctrine considered, p. 78, 79. Whether fluid bodies are made from parts originally fluid, or from small Solids in motion, &c. p. 79, 80, 81. Mr. Hobbs's Theory of Fluidity and Firmness examined, p. 81, 82, &c. What influence therein his simple circular motion may have, considered, p. 82, 83. That there is a third requisite of a good Hypothesis, viz. That it be not inconsistent with any Truth or Phaenomenon of Nature, p. 84. That Mr Hobbs his Hypo∣thesis wants this requisite, proved by references, p. 85. By instances out of ordinary, not elaborate, Experiments, p. 86. The Conclusion to the Reader, p. 88.