Treya Meynack in the Western Air: An Tir Gallósek The Mighty Land Book Three

Treya lives in in the underground realm of Caer Hudol, where until recently she was one of the An Dhew, a gender-nuetral service collective. Treya has a good life, but she longs to travel to the surface. When Philippa and Arghan come to visit, Treya returns to Kernow with them. Adjusting to the surface is difficult at first. After a bit of drama, she settles in to her new life, befriending Lady Borlowan, a royal attendant, as well as the charming but mysterious Marianis brothers. She uses her climbing skills to help build Trevena's bridge, and she becomes a scribe in the King's Archive, under the elderly and quirky Master Skell. Together, Treya and Philippa revive the practice of augery: finding relevant meaning in the activities of birds.

Before long, the companions are caught up in a quest that takes them up the coast to the hill-fort of Dinas Dinlle. There they hope to find a seemingly invisible tower, and a map to lead them to the mythical land of Thule, to search for a long-lost king.

Excerpt, Chapter 5 - Auspicious Portents (Treya and Pippa perform an Augery in advance of their upcoming journey.) Pippa stood facing the sea, and the open horizon. Treya faced the hills, and the cliffs that bordered the west side of Trevena castle... She and Pippa stood in silence, back to back, hoods up, each peering into their own templum in the sky that they had mapped out with their spiral wands. According to Occul of Lugdunen, there were conflicting cultural views over whether an Auger should face north or south, so they had decided that since they were a team, they would do both, and compare their findings.
Treya drew a long slow breath and focused her attention. She could hear distant gulls, crying loudly all of a sudden, but no birds had appeared in her quadrant. As she gazed, her mind wandered back to the time she had spent on the peaks over the Red Sands. She recalled the hazy ceiling of the cavern, and the birds that wheeled around near the sky-cracks. Compared to the pale fish-catchers that populated the underground world, they had looked very large. At the time, with their silver-grey plumage and shiny green heads, they had seemed exotic to her. Now she realized that they were common doves. She still thought that they were beautiful, but she understood that they were not considered very exotic at all by most surface-dwellers.
The cries of the gulls became more insistent. Then Treya realized why. A white-tailed sea-eagle had appeared in her templum, flying diagonally from lower left to upper right. An eagle! Treya thought. The most auspicious of all the birds, flying left to right. Beginning in the realm of instinct, and becoming rarified through reason.
Then another sea-eagle appeared! It came from the lower right, and flew towards the upper left. Right to left: reason is limited until it embraces instinct. Then they were gone from view.

Excerpt, Chapter 20 - Waiting for the Stars (Sailing the northern waters)
"ICE!" screamed Piri from above. "Ice to starboard."
"Ice to port!" cried Brutus. "DROP MAINSAIL!" bellowed Santo. "RAISE FORESAIL!"
Arghan and Piran scrambled to unhitch the mainsail. Then they very quickly installed the little navigation sail, connected it to the tiller-rig, and raised it. The ship slowed to a crawl.
It was a strange site. Long narrow drifts of ice were floating on the water. Some were very tiny, and easy for the ship to push out of the way. Others created obstacles of long frozen slabs, which were covered with tall conical ice formations. The cone-shapes were blobby, like huge drippy sand castles of frozen water.
The skipper was standing. He navigated very slowly around the long slabs, his eyes on the water ahead. At the base of the slabs, the ice spread out thinly, reaching out in tendrils that were so delicate that some broke off as they were hit by the gentle wake of the slowly moving ship.