j 6 DIURNAL MOVEMENT. 



Nature, transformed by the ancients into a multiple divinity, 

 never fails to overwhelm with surprise the observer who in- 

 terrogates her with simplicity and without any preconcerted 

 system. And it was thus that he who first undertook to 

 enumerate the stars, by the help of the constellations, made 

 at once the greatest and most unexpected discovery. What, 

 in fact, was not his astonishment on seeing the gradual dis- 

 placement of objects which, at the first glance, appeared 

 immovable ! 



To this very natural astonishment soon succeeded, we doubt 

 not, a desire to analyse the phenomenon. The most beautiful 

 constellations of the firmament, Ursa and Orion, will have 

 their points of repery on the star-gemmed sphere. An atten- 

 tive study, eagerly pursued through a certain lapse of time, 

 would teach him that Orion rises and sets like the sun and 

 the moon, while the Bear, remaining perpetually above the 

 horizon, neither rises nor sets. Stimulated by curiosity, the 

 observer would afterwards assure himself that the whole of 

 the celestial vault revolved upon an axis, while the stars 

 divided into groups; remain fixed, fixed in this sense, that 

 they constantly maintain among themselves the same relations 

 of distance. The idea of a solid sphere, to which the stars 

 were attached like golden nails, then came quite naturally 

 to the human mind. Such, undoubtedly, was the origin of 

 the. discovery of diurnal movement; of that general movement 

 which carries all the stars from west to east, to bring them 

 back to the same points in the course of one complete day. 



To hear our professors of astronomy invariably repeating, 



