Great Tom, tolling his nightly hundred-and-one

From Gaudy Night by Dorothy L. Sayers.  Page 242.

April was running out, chilly and fickle, but with the promise of good things to come; and the city wore the withdrawn and secretive beauty that wraps her about in vacation. No clamour of young voices echoed along her ancient stones; the tumult of flying bicycles was stilled in the narrow strait of the Turf; in Radcliffe Square the Camera slept like a cat in the sunshine, disturbed only by the occasional visit of a slow-footed don; even in the High, the roar of car and charabanc seemed diminished and brought low, for the holiday season was not yet; punts and canoes, new-fettled for the summer term, began to put forth upon the Cherwell like the varnished buds upon the horse-chestnut tree, but as yet there was no press of traffic upon the shining reaches; the mellow bells, soaring and singing in tower and steeple, told of time’s flight through an eternity of peace; and Great Tom, tolling his nightly hundred-and-one, called home only the rooks from off Christ Church Meadow.

Great Tom and the tolling one 101?  From Wikipedia:

Great Tom is still sounded 101 times every night, which signifies the 100 original scholars of the college plus one (added in 1663). It is rung at 21:05 current UK time, which corresponds to 21:00 in what used to be "Oxford time" (local mean time for Oxford, noon in Oxford always occurring five minutes later than noon in Greenwich), and was at one time the signal for all the Oxford colleges to lock their gates. The bell is only rung by swinging on very special occasions.