64 GALILEO AND HIS JUDGES, 



gladly be corrected if in error. Simplicio's mathematical 

 acquirements are not very great, and it is necessary 

 to explain to him that the areas of circles vary in 

 proportion, not to their diameters simply but to the 

 squares of the diameters, a point which arises in 

 reference to the false judgment formed by the naked 

 eye as to the size of the celestial bodies, an error 

 which is corrected by the telescope. Then to those 

 who made it a difficulty that the Earth should move 

 round the Sun, not alone, but accompanied by the 

 Moon, Salviati is made to reply that Jupiter revolves 

 round the Sun accompanied by four moons. 



Again the greater simplicity of the Copernican 

 theory, in accounting for the planetary motions, as 

 they appear to us, is expounded by the same 

 personage. 



Galileo occasionally makes the interlocutors allude 

 to himself as "il nostro amico comune," "il nostro 

 Accademico Linceo," etc., and thus claims credit for 

 having been the first to discover the solar spots, a 

 credit which ought not to belong exclusively to him, 

 as Fabricius and the Jesuit Father Scheiner saw the 

 spots at about the same time. 



An argument is here attempted to be drawn in 

 favour of the Earth's annual motion from the apparent 

 course of the Sun-spots, and the curves they some* 

 times describe (as viewed from hence), owing to the 

 inclination of the Sun's axis to an axis perpendicular 

 to the plane of the ecliptic an inclination of about 

 7 ; there is nothing, however, at all conclusive in 



