Which preposition to use with rythms

with Occurrences 2%

The noise is phenomenal, overpowering, but is plainly attractive to Sidi ears; for the room is rapidly filling, and more than one of the spectators suddenly leaps from his seat and circles round the drummers, keeping time to the rythm with queer movements of his body and feet and whirling a "lathi" round his head in much the same fashion as the proverbial Irishman at Donneybrook Fair.

of Occurrences 1%

It bears the unmistakable marks of weal and woe of Norse life, the strongly marked and regularly introduced rythms of the developed and developing national character.

Which preposition to use with  rythms