Cliap. 99.] CAUSE OF THE TIDES. 125 



always in the space of twenty-four hours. First, the moon 

 rising with the stars ^ swells out the tide, and after some time, 

 having gained the summit of the heavens, she declines from 

 the meridian and sets, and the tide subsides. Again, after she 

 has set, and moves in the heavens under the earth, as she 

 approaches the meridian on the opposite side, the tide flows 

 in ; after which it recedes until she again rises to us. But 

 the tide of the next day is never at the same time with that of 

 the preceding ; as if the planet was in attendance^, greedily 

 drinkiug up the sea, and continually rising in a different place 

 from what she did the day before. The intervals are, however, 

 equal, being always of six hours ; not indeed in respect of any 

 particular day or niglit or place^, but equinoctial hoiu's, and 

 therefore they are unequal as estimated by the length of com.- 

 mon hours, since a greater number of them"^ fall on some cer- 

 tain days or nights, and they are never equal everywhere 

 except at the equinox. This is a great, most clear, and even 

 divine proof of the dullness of those, who deny that the stars 

 go below the earth and rise up again, and that nature pre- 

 sents the same face in the same states of their rising and 

 setting^ ; for the course of the stars is equally obvious in the 

 one case as in the other, producing the same effect as when 

 it is manifest to the sight. 



There is a difference in the tides, depending on the moon, 

 of a complicated nature, and, first, as to the period of seven 

 days. For the tides are of moderate height from the new 

 moon to the ffrst quarter ; from this time they increase, and 

 are the highest at the full: they then decrease. On the 

 seventh day they are equal to what they were at the first 



^ " Mundo ;" the heavens or visible firmament, to which the stara and 

 planets appear to be connected, so as to be moved along with it. 



2 " Ancillante ; " " Credas ancillari sidus, et iudiilgere mari, vit non ab 

 eadem parte, qua pridie, pastum ex oceano haui'iat." Ilardouin in 

 Lemaire, i. 427. 



3 Not depending on the time of the rising and setting of the sun or 

 the latitude of the place, but determmate portions of the diurnal pei'iod. 



^ By a conjectural variation of a letter, viz. by substituting "eos" for 

 " eas," Dalechairip has, as he conceives, i*endercd tliis passage more clear; 

 the alteration is adopted by Lemau'e. 



* "In iisdem ortus occasusque operibus;" "Eodem modo utrinquo 

 oricntibus occidentibusque sideribus," as interpreted by Alexandre iu 

 Lemaire, i. 428. 



