**  A second window aside called by the
She-philosopher.com Players page for Robert Hooke, entitled
“The Absent Presence of Robert Hooke”  **

First Published:  March 2012
Revised (substantive):  5 July 2021

A NOTE ON THE DIGITAL TRANSCRIPT THAT FOLLOWS:
Each part of Derham’s printed transcription of Hooke’s December 1696 three-part lecture on the nautilus opened with an introductory note signed by Derham.

---

[  read to the Royal Society on 16 December 1696  ]

P A R T   T W O   O F

Dr. Hook’s Conjectures
about the Odd Phaenomena Observable in the Shell-Fish
Called the Nautilus

“ On Dec. 16. following, Dr. Hook resum’d his Considerations of the Nautilus, and having taken Notice of several Transmutations, as particularly of Water into the solid Parts of Vegetables, as also into Earth or Ice; he then proceeds, and saith,

“ W.   D E R H A M.

 

“ The Account which Dr. Hook gives is thus:

BUT this Metamorphosis, or Transmutation of Elements, I take Notice of here, only by the by, as it may be of some Use for the Explication of another Metamorphosis of a contrary Nature, and that is, of Water into Air, which is by Rarefaction, for such an Operation Nature seems to have; and somewhat of this Kind is producible by Art, as has been prov’d to this Society by many Experiments, heretofore made, for the Production of artificial Air; which, though under that Notion it seem’d not to be regarded, yet, as such another, published a good While after all those Experiments, as his own, not owning at all he had been inform’d of them, by some of the Members of this Society: But to pass by that at present (because there are Abundance of Instances of the like Nature that have been given, which I may on some other Occasions manifest) I had a further Prospect in the Success of those Trials than what was, for the like Reasons, then spoken of; one of which was, for the Solution of such a Phenomenon as this, of the floating and sinking of the Nautilus, which I discoursed of the last Meeting but one. It seem’d, indeed, very strange, how that Creature could so, at his Will fill, and empty, the Cavities of his Shell, with Water; it was easy to conceive, how he could fill his Shell with Water, and so sink himself to the Bottom; but then how (when there, at such a Distance, from the Air) he could evacuate the Water, and fill the Cavities with Air, that was difficult to comprehend, especially being under so great a Pressure of Water: But if Nature had furnish’d him with a Faculty of producing an artificial Air, then the Riddle would quickly be unfolded. I found, therefore, that by Art it was feasable to produce such an artificial Air, and that it was endued with a very great Power of Expansion, so that it would not only make itself Room to expand, notwithstanding the incumbent Pressure of the Air on all Sides; but, if sealed up in strong Glasses, it would break out the Sides there of, which might have as much Power of Expansion as might counterpoise, nay, out-power both the Pressure of the Air, and also the Water too, though 100 Times greater than that of the Air. It will be, I confess, a difficult Matter for me to prove, that the Nautili have such a Power, for that I could never yet get a Sight of that Fish that inhabits those Shells, nor do I find that any of the Authors, that pretend to describe it, have, nor has any of them given a Description of it that can give one any true Idea of it: Yet, methinks, it might be procured from some ingenious Person, that has an Opportunity of visiting the Barbadoes, and some of the other Leeward Islands, where there are found great Plenty of a smaller Sort of them, which though of a differing Shape, in the Coil of the conical Body, yet they agree with all the other Kinds of them in having the Diaphragms, and a Ductus, or Vessel passing through them all, from the Basis to the Apex of the coiled Cone, and the Axis of that Cone is also coiled in a Plane, as are all the other Kinds of the Nautili; of which I have one here to shew, given me by one who had a whole Box full of them, which he had there collected, and brought with him to England.

---

SOURCE:  The above lecture text was first transcribed and printed by William Derham in Philosophical Experiments and Observations of the Late Eminent Dr. Robert Hook ... and Other Eminent Virtuoso’s in his Time (London: Printed by W. and J. Innys, printers to the Royal Society, 1726), 309–311.