Amidst the many felicities that have accompani’d your Majesties happy Restauration and Government, it is none of the least considerable that Philosophy and Experimental Learning have prosper’d under your Royal Patronage.  And as the calm prosperity of your Reign has given us the leisure to follow these Studies of quiet and retirement, so it is just, that the Fruits of them should, by way of acknowledgement, be return’d to your Majesty.  There are, Sir, several other of your Subjects, of your Royal Society, now busie about Nobler matters:  The Improvement of Manufactures and Agriculture, the Increase of Commerce, the Advantage of Navigation:  In all which they are assisted by your Majesties Incouragement and Example.  Amidst all those greater Designs, I here presume to bring in that which is more proportionable to the smalness of my Abilities, and to offer some of the least of all visible things, to that Mighty King, that has establisht an Empire over the best of all Invisible things of this World, the Minds of Men.

Your Majesties most humble and most obedient Subject and Servant,

ROBERT HOOKE.

* * * * *

TO THE

ROYAL SOCIETY.

After my Address to our Great Founder and Patron, I could not but think my self oblig’d, in consideration of those many Ingagements you have laid upon me, to offer these my poor Labours to this MOST ILLUSTRIOUS ASSEMBLY.  YOU have been pleas’d formerly to accept of these rude Draughts.  I have since added to them some Descriptions, and some Conjectures of my own.  And therefore, together with YOUR Acceptance, I must also beg YOUR pardon.  The Rules YOU have prescrib’d YOUR selves in YOUR Philosophical Progress do seem the best that have ever yet been practis’d.  And particularly that of avoiding Dogmatizing, and the espousal of any Hypothesis not sufficiently grounded and confirm’d by Experiments.  This way seems the most excellent, and may preserve both Philosophy and Natural History from its former Corruptions.  In saying which, I may seem to condemn my own Course in this Treatise; in which there may perhaps be some Expressions, which may seem more positive then YOUR Prescriptions will permit:  And though I desire to have them understood only as Conjectures and Quaeries (which YOUR Method does not altogether disallow) yet if even in those I have exceeded, ’tis fit that I should declare, that it was not done by YOUR Directions.  For it is most unreasonable, that YOU should undergo the imputation of the faults of my Conjectures, seeing YOU can receive so small advantage of reputation by the sleight Observations of