NOVUM ORGANUM 199 



a real motion of revolution in the heavenly bodies, or only 

 apparent in them, and real in the earth. There may be an 

 instance of the cross of the following nature. If there be 

 discovered any motion in the ocean from east to west, 

 though very languid and weak, and if the same motion be 

 discovered rather more swift in the air (particularly within 

 the tropics, where it is more perceptible from the circles 

 being greater). If it be discovered also in the low comets, 

 and be already quick and powerful in them; if it be found 

 also in the planets, but so tempered and regulated as to be 

 slower in those nearest the earth, and quicker in those at 

 the greatest distance, being quickest of all in the heavens, 

 then the diurnal motion should, certainly be considered as 

 real in the heavens, and that of the earth must be rejected; 

 for it will be evident that the motion from east to west is 

 part of the system of the world and universal; since it 

 is most rapid in the height of the heavens, and gradually 

 grows weaker, till it stops and is extinguished in rest at 

 the earth. 



Again, let the required nature be that other motion of 

 revolution, so celebrated among astronomers, which is con 

 trary to the diurnal, namely, from west to east and which 

 the ancient astronomers assign to the planets, and even to 

 the starry sphere, but Copernicus ^.nd his .followers to the 

 earth also and let it be examined whether any such motion 

 be found in nature, or it be rather a fiction and hypothesis 

 for abridging and facilitating calculation, and for promoting 

 that fine notion of effecting the heavenly motions by perfect 

 circles; for there is nothing which proves such a motion in 

 heavenly objects to be true and real, either in a planet s not 

 returning in its diurnal motion to the same point of the 

 starry sphere, or in the pole of the zodiac being different 



