Diagrams
Date
20 August 1670
Creator
Unknown, Artist
Object type
Archive reference number
Manuscript page number
vol4 p64
Material
Dimensions
height (page): 301mm
width (page): 175mm
width (page): 175mm
Subject
Content object
Description
The top figure is a diagram originally used by Descartes to determine the limits of the primary and secondary rainbows, in angular measure from the observer's eyes. In his letter to Henry Oldenburg dated 20 August 1670, Franciscus Renatus Slusius suggested that he could find the solution by experimenting on a glass globe full of water. Slusius asked Oldenburg to transmit this solution to Isaac Barrow, who was doubtful of its accuracy.
The second figure illustrates the problem proposed by Slusius: in the semicircle AGB, whose centre is C, so to inflect a straight line GF from the given point G that the two perpendiculars FH on AB, and CE on FG, have a given ratio to each other (as translated in Correspondence of Henry Oldenburg, vol. 7, p. 118).
The figures were copied from LBO/4/048-049. The figures in the original letter at EL/S1/65/001-002.
The second figure illustrates the problem proposed by Slusius: in the semicircle AGB, whose centre is C, so to inflect a straight line GF from the given point G that the two perpendiculars FH on AB, and CE on FG, have a given ratio to each other (as translated in Correspondence of Henry Oldenburg, vol. 7, p. 118).
The figures were copied from LBO/4/048-049. The figures in the original letter at EL/S1/65/001-002.
Related fellows
Renatus Franciscus Slusius (1622 - 1685, Belgian) , Mathematician
Henry Oldenburg (1612 - 1677, German) , Scientific correspondent
Henry Oldenburg (1612 - 1677, German) , Scientific correspondent
Associated place