BOOK II. uv. 140-LV. 142 



altars and rites, and among the other Jupiters, the 

 Stayers and Thunderers and Receivers of Offerings,* 

 tradition gives us Jupiter the Invoked. On this 

 matter the opinion of mankind varies, in corre- 

 spondence with our individual dispositions. It takes 

 a bold man to beHeve that Nature obeys the behests 

 of ritual, and equally it takes a dull man to deny 

 that ritual has beneficent powers, when knowledge 

 has made such progress even in the interpretation 

 of thunderbolts that it can prophecy that others 

 vvill come on a fixed day, and whether they will 

 destroy a previous one or other pre\aous ones 

 that are concealed : this progress has been made 

 by public and private experiments in both fields. 

 In consequence although such indications are 

 certain in some cases but doubtful in othei's, and 

 approved to some persons but in the view of others 

 to be condemned, in accordance with Nature's will 

 and pleasure, we for our part are not going to leave 

 out the rest of the things worth recording in this 

 department. 



LV. It is certain that when thunder and lightning Thunder a 

 occur simultaneously, the flash is seen before the ^idhtning. 

 thunderclap is heard (this not being surprising, as 

 light travels more swiftly than sound) ; but that 

 Nature so regulates the stroke of a thunderbolt and 

 the sound of the thunder that they occur together, 

 although the sound is caused by the bolt starting, 

 not striking ; moreover that the current of air 

 travels faster than the bolt, and that consequently 

 the object always is shaken and feels the blast before 

 it is struck ; and that nobody hit has ever seen the 

 lightning or heard the thunder in advance. Flashes 

 on the left are considered lucky, because the sun 



279 



