Then there were tiny wisps of cloud, more delicate and frail than feathers or the down of a dandelion-blow.  Chasms hundreds of feet deep, sheer columns, and banks, extended almost beyond eye-reach. Between the flyers and the sun stretched isolated towers of cumulus, cast up as if erupted by the chaos below.  The sunlight, filtering through this or that gossamer bulk, was scattered into every conceivable shade and monotone.  And around the margins of the heaving billows the sun's rays played unhampered, unrestricted, outlining all with edgings of the purest silver.