This week we posted an Objectivity video featuring Dr James Grime visiting the Royal Society.
Head librarian Keith Moore showed James an intriguing object - an ornamental piece purporting to prove that a circle can indeed be squared.
Sent by a chap named Charles Hudson, based in Calcutta, it was said to show "the solution and demonstration of the quadrature of the circle".
At the time of filming, we did not have the object's accompanying documents.
But, by popular demand, Keith has dug up some correspondence and made it available to us.
You can download it as a PDF here, or see the photo gallery below.
But you may have to transcribe the handwriting yourself. We can't do everything for you.
And of course, as James himself told us on Numberphile, the whole endeavour was later proven to be impossible.