Transverse scale for astronomical observation
                                Date
                            
                            
                                31 December 1673
                            
                            
                        
                            
                            
                            
                                Creator
                            
                            
                                Unknown, Artist
                            
                            
                        
                            
                            
                            
                                Object type
                            
                            
                            
                        
                            
                            
                            
                                Archive reference number
                            
                            
                            
                        
                            
                            
                            
                                Manuscript page number
                            
                            
                                vol6 p424
                            
                            
                        
                            
                            
                            
                                Material
                            
                            
                            
                        
                            
                            
                            
                                Dimensions
                            
                            
                                height (page): 303mm
width (page): 178mm
                            
                        
                            
                            
                            width (page): 178mm
                                Subject
                            
                            
                            
                        
                            
                            
                            
                                Description
                            
                            
                                Diagram of a transverse scale.
Johannes Hevelius’s Machina coelestis pars prior (Gdansk: S. Reiniger for J. Hevelius, 1673), included descriptions of the instruments Hevelius used for his astronomical observations. These included open-sighted astronomical instruments using transversal scales. Robert Hooke, in his Animadversions on the first part of the machine Coelestis (London: T.R. for John Martyn, 1674), criticised Hevelius for not using telescopic sights, given the limitations of human eyesight. In his letter dated 31 December 1673, John Wallis offered a mathematical justification for the use of transversal scales in this letter, thus siding with Hevelius in the subsequent dispute between Hooke and Hevelius about the appropriate instrument for accurate astronomical observations.
This diagram is a copy of the one at LBO/6/353. It occurs in the original letter at EL/W2/16/002.
                            
                            
                        
                            
                            
                            Johannes Hevelius’s Machina coelestis pars prior (Gdansk: S. Reiniger for J. Hevelius, 1673), included descriptions of the instruments Hevelius used for his astronomical observations. These included open-sighted astronomical instruments using transversal scales. Robert Hooke, in his Animadversions on the first part of the machine Coelestis (London: T.R. for John Martyn, 1674), criticised Hevelius for not using telescopic sights, given the limitations of human eyesight. In his letter dated 31 December 1673, John Wallis offered a mathematical justification for the use of transversal scales in this letter, thus siding with Hevelius in the subsequent dispute between Hooke and Hevelius about the appropriate instrument for accurate astronomical observations.
This diagram is a copy of the one at LBO/6/353. It occurs in the original letter at EL/W2/16/002.
                                Related fellows
                            
                            
                                John Wallis (1650, British) , Mathematician
Johannes Hevelius (1611 - 1687, German/Polish) , Astronomer
                            
                        
                            
                            
                            Johannes Hevelius (1611 - 1687, German/Polish) , Astronomer
                                Associated place