| Description | Rix cannot tell if it would be worth de Haan's while to have the extract to which he refers from their Register Book copied, but he summarises it so that he can judge for himself. He explains that the letter from Huygens to Oldenberg dated 5 January 1669, of which they possess the original, is endorsed - "Monsr Huygens letter to Mr Oldenb. concerning the laws of M[?] sent by him for the R. Society; and to be found registered in this Register Book".
Rix states that the entry in the Register Book IV p.36 which he wants a copy of is an inclosure which would have been sent in the aforementioned letter. It is 8 folio pages long with illustrations. It is annotated in the margins with a reference to 'Philosophical Transactions of the Royal Society', volume 4, number 4[?] p935. The summary in 'Philosophical Transactions' is not a transcript of the entry in their Register Book though, but might be an abstract of it. |