Ever hopeful of rabbit and fox, Billy urged on his cheerful waddling pack and the sea wind rang with the crack of his whip and the treble note of his whistle.  Drina, lately inoculated with the virus of nature-study, carried a green gauze butterfly net, while Boots’s pockets bulged with various lethal bottles and perforated tin boxes for the reception of caterpillars.  The other children, like the puppies of Billy’s pack, ran haphazard, tireless and eager little opportunists, eternal prisoners of hope, tripped flat by creepers, scratched and soiled in thicket and bog, but always up and forward again, ranging out, nose in the wind, dauntless, expectant, wonder-eyed.

Nina, Eileen, and Selwyn formed a lagging and leisurely rear-guard, though always within signalling distance of Boots and the main body; and, when necessary, the two ex-army men wig-wagged to each other across the uplands to the endless excitement and gratification of the children.

It was a perfect week-end; the sky, pale as a robin’s egg at morn and even, deepened to royal blue under the noon-day sun; and all the world—­Long Island—­seemed but a gigantic gold-green boat stemming the running purple of the sea and Sound.

The air, when still, quivered in that deep, rich silence instinct with the perpetual monotone of the sea; stiller for the accentless call of some lone moorland bird, or the gauzy clatter of a dragon-fly in reedy reaches.  But when the moon rose and the breeze awakened, and the sedges stirred, and the cat’s-paws raced across the moonlit ponds, and the far surf off Wonder Head intoned the hymn of the four winds, the trinity, earth and sky and water, became one thunderous symphony—­a harmony of sound and colour silvered to a monochrome by the moon.

Then, through the tinted mystery the wild ducks, low flying, drove like a flight of witches through the dusk; and unseen herons called from their heronry, fainter, fainter till their goblin yelps died out in the swelling murmur of a million wind-whipped leaves.

Then was the moorland waste bewitching in its alternation of softly checkered gray and shade, where acres of feathery grasses flowed in wind-blown furrows; where in the purple obscurity of hollows the strange and aged little forests grew restless and full of echoes; where shadowy reeds like elfin swords clattered and thrust and parried across the darkling pools of haunted waters unstirred save for the swirl of a startled fish or the smoothly spreading wake of some furry creature swimming without a sound.

Into this magic borderland, dimmer for moonlit glimpses in ghostly contrast to the shadow shape of wood and glade, Eileen conducted Selwyn; and they heard the whirr of painted wood-ducks passing in obscurity, and the hymn of the four winds off Wonder Head; and they heard the herons, noisy in their heronry, and a young fox yapping on a moon-struck dune.

But Selwyn cared more for the sun and the infinite blue above, and the vast cloud-forms piled up in argent splendour behind a sea of amethyst.