Since my writing this letter I am told by one who had it from another lately present at one of yoryour meetings, how that Mr Hook should there make a great stir pretending I had all from him & desiring they would see that he had justice done him. This carriage towards me is very strange & undeserved, so that I cannot forbeare in stating ytthat point of justice to tell you further, that he has published Borell's Hypothesis in his own name & the asserting of this to himself & completing it as his own, seems to me the ground of all yethe stir he makes. Borel did something in it & wrote modestly, he has such a way done nothing & yet written in such a way as if he knew & had sufficiently hinted all but what remained to be determined by yethe drudgery of calculations & observations, excusing himself from that labour by reason of his other business: whereas he should rather have excused himself by reason of his inability. For tis plain by his words he knew not how to go about it. Now is not this very fine? Mathematicians that find out, settle & do all the business must content themselves with being nothing but dry calculators & drudges & another that does nothing but pretend & grasp at all things must carry away all the invention as55– as well of those that were to follow him as of those that went before. Much after the same manner were his letters writ to me, telling me that gravity in descent from hence to yethe center of yethe earth was reciprocally in a duplicate ratio of yethe altitude, that yethe figure described by projectiles in this region would be an Ellipsis & that all yethe motions of yethe heavens were thus to be accounted for: & this he did in such a way as if he had found out all & knew it most certainly. And upon this information I must now acknowledge in print I had all from him & so did nothing my self but drudge in calculating demonstrating & writing upon yethe inventions of this great man. And yet after all, the first of those three things he told me is fals & very unphilosophical, the second is as fals & yethe third was more then he knew or could affirm me ignorant of by any thing that past between us in orour letters. Nor do I understand by wtwhat right he claims it as his own. For as Borell wrote long before him that by a tendency of yethe Planets towards yethe sun like that of gravity or magnetism the Planets would move in Ellipses, so Bullialdus wrote that all force respecting yethe Sun as its center & depending on matter must be reciprocally in a duplicate ratio of yethe distance from yethe center, & used that very argument for it by wchwhich you, SrSir, in the last Transactions have proved this ratio in gravity. Now if Mr Hook from this general Proposition in Bullialdus might learn yethe proportion in gravity, why must this proportion here go for his invention? My letter to Hugenius wchwhich I mentioned above was directed to Mr Oldenburg who used to keep yethe Originals. His papers came into Mr Hooks possession. Mr Hook knowing my hand might have yethe curiosity to look into that letter & thence take yethe notion of comparing yethe forces of yethe Planets arising from their circular motion & so what he wrote to me afterwards about yethe rate of gravity, might be nothing but yethe fruit of my own Garden. And its more then I can affirm ytthat yethe duplicate proportion was not exprest in that letter. However he knew it not (ias I gather from his books) till five years after any Mathematician could have told it him. For when Hugenius had told how to find yethe force in all cases of circular motion, he had told 'emthem how to do it in this as well as all others. And so yethe honour of doing it in this way is due to Hugenius. For another five years after to claim it as his own invention, is as if some Mechanick who had learnt yethe Art of surveying from a Master should afterwards claim the surveying of this or that piece of ground for his own invention & keep a heavy quarter to be in print for 'tit. But what if this surveyor be a bungler & give in an erroneous survey? Mr Hook has erred in the invention he pretends to & his error is yethe cause of all the stirr he makes. For his extending yethe duplicate proportion down to yethe center (which I do not) made him correct me & tell me yethe rest of his Theory as a new thing to me & now stand upon it that I had all from that his letter: notwithstanding that he had told it to all yethe world before & I had seen it in his printed books all but yethe proportion. And why should I record a man for an Invention who founds his claim upon an error therein & on that score gives me trouble? He imagins he obliged me by telling me his Theory, but I thought my self disobliged by being upon his own mistake corrected magisterially & taught a Theory wchwhich every body knew & I had a truer notion of then himself. Should a man who thinks himself knowing, & loves to shew it in correcting & instructing others, come to you when you are busy, & notwithstanding your excuse, press discourses upon you & through his own mistakes pr correct you & multiply discourses & then make this use of it, to boast that he taught you all he spake & oblige you to acknowledge it & cry out injury & injustice if you do not, I beleive you would think him a man of a strange unsociable temper. Mr Hooks letters in several respects abounded too much wthwith that humour wchwhich Hevelius & others complain of & therefore he may do well in time to consider whether after this new provocation I be much more bound (in doing him that justice he claims) to make an honourable mention of him in print, especially since this is yethe third time that he has given me trouble in this kind.