Quarrier's mania was Tandem.

She thought it rather nice of her to remember this.
She inspected the ensemble without visible interest for a few moments; the wind freshened from the sea, fluttering her veil, and she turned toward the east to face it.

In the golden splendour of declining day the white sails of yachts crowded landward on the last leg before beating westward into Blue Harbour; a small white cruiser, steaming south, left a mile long stratum of rose-tinted smoke hanging parallel to the horizon's plane; the westering sun struck sparks from her bright-work.
The magic light on land and water seemed to fascinate the girl; she had walked a little way toward the cliffs, Siward following silently, offering no comment on the beauty of sky and cliff.

As they halted once more the enchantment seemed to spread; a delicate haze enveloped the sea; hints of rose colour tinted the waves; over the uplands a pale mauve bloom grew; the sunlight turned redder, slanting on the rocks, and every kelp-covered reef became a spongy golden mound, sprayed with liquid flame.
They had turned their backs to the Tandem; the grooms looked after them, standing motionless at the horses' heads.
"Mr.Siward, this is too fine to miss," she said.

"I will walk as far as the headland with you.