Which preposition to use with pyles

of Occurrences 2%

35 First, th'Earth, on adamantine pillers founded Amid the Sea, engirt with brasen bands; Then th'Aire, still flitting, but yet firmely bounded On everie side with pyles of flaming brands, Never consum'd, nor quencht with mortall hands; 40 And last, that mightie shining cristall wall, Wherewith he hath encompassed this all.

Which preposition to use with  pyles