Reference numberCLP/1/14
TitlePaper, 'To find two mean proportionalls betweene two straight lines given' by [Thomas Hobbes]
Date[17th century]
DescriptionTo find two mean proportionals between two straight lines given.

At the meeting of the Royal Society on 4 September 1661, Sir Paul Neile brought in a paper, endorsed by the King, of Thomas Hobbes's proposal for how to double the cube (stated as finding two proportionals between two straight lines given). This diagram is from Hobbes's proof. William Brouncker was asked to examine the proof, which he here showed was erroneous.

Includes equations and a diagram.

Subject: Geometry
Physical descriptionInk on paper
Digital imagesView item on Science in the Making
Access statusOpen
Related records in the catalogueRBO/1/20
Fellows associated with this archive
NA3503Brouncker; William (c1620 - 1684); 2nd Viscount Brouncker; mathematicianc1620 - 1684
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