Which preposition to use with runnels

of Occurrences 7%

II SIEVE OF FULFILMENT How constant a stream is the runnel of men's small affairs!

at Occurrences 1%

Its situation is remarkable for the impartiality of its maritime predilections, for the runnels at the side of the thoroughfare are said to discharge their contents, the one into the Bristol, the other into the English Channel.

in Occurrences 1%

At about the nine thousand foot level and in the summer there will be hosts of rosy-winged dodecatheon, called shooting-stars, outlining the crystal runnels in the sod.

Which preposition to use with  runnels