TWO THO US AND YEARS AGO. 113 



a reason, but it was certainly true as a sentiment. As every- 

 body knows, it was Voltaire who first removed the prohibition, 

 and popularised the Newtonian philosophy in France. 



How did our astronomers finally succeed in demonstrat- 

 ing mathematically the veritable form of our planet ? 



To obtain a clear and accurate conception, we are obliged 

 to transport ourselves back two thousand years. Let us 

 recall, in the first place, that, owing to the diurnal move- 

 ment, all the stars progress from east to west ; that they 

 rise and set, to recommence the same rotation. This is 

 a general and conspicuous fact, which everybody can con- 

 firm for himself. But now for another, whose observation 

 requires a little more time and patience. During the diurnal 

 movement, which carries on all the stars and the sun him- 

 self, the latter progresses independently, in the inverse 

 direction of the celestial vault, as a fly might do upon a 

 revolving globe. But this second fact is complicated with 

 a third: While advancing on his own account, from west 

 to east, the circle which the sun traverses is not parallel 

 to the Equator; the radiant luminary transports himself 

 alternatively into the northern and southern hemispheres, 

 accomplishing this rotation in 365 days and a fraction of a 

 day, in an oblique plane, which cuts that of the Equator 

 under an angle of about 23^. 



Let us here take advantage of a parenthesis to explain a 

 few astronomical technicalities, necessary for the due compre- 

 hension of our subject. 



