Treasury Day was a holiday celebrated by Sanctaphrax academics to commemorate the exile of the Earth-Scholars. It occurred every year on the first day of the second moon in its third quarter. On this day, the Next-Most High Academe would journey down the Sanctaphrax Tunnel into the Treasury Chamber and recite a ceremonial saying while gazing upon the stormphrax. This ceremony would be followed by joyous feasting and gift-swapping. Quint and Maris observed the ceremony in The Curse of the Gloamglozer and Quint participated in it in The Winter Knights.
When the Sanctaphrax rock gained buoyancy, the earth-studies librarians wanted to solve the problem by studying the rock's properties and then coming to a solution. The sky-scholars however proposed to weigh down the rock with stormphrax, thus violating the Third Law of Buoyancy. To ensure the survival of the floating city, the sky-scholars enlisted a band of flat-head goblins that was later to become the Treasury Guard. Then, on the first day of the second moon in its third quarter, the goblins violently forced the librarians to leave the Great Library of Sanctaphrax and by noon, the sky-scholars were in control of the city. A chest filled with stormphrax was then carried into the centre of the Sanctaphrax Rock, the Treasury Chamber. This was carried out by the Next-Most High Academe, a sky-scholar, because at the time of the Great Purges, an earth-scholar was the Most High Academe of Sanctaphrax.
Certain aspects of that event remained and became part of a tradition of celebrating Treasury Day. In the refectory, the day was celebrated with a seven-course meal and many swapped gifts and sent messages. Crowds would also gather at the entrance of the Sanctaphrax Tunnel to watch the Next-Most High Academe inspect the Sanctaphrax. The Knights Academy would also make an appearance, the squires from both the Lower and the Upper Halls marching ahead in silver helmets and long cloaks, behind them the hall servants and the knights academic-in-waiting in shining armour. At exactly three hours, the Next-Most High Academe's prowlgrin-drawn carriage would roll onto the Quadrangle Mosaic. Exactly seven steps away from the pyramid-shaped entrance the Next-Most High Academe would step on the red and gold carpet. They would knock the entrance door three times with their stave and guard would then answer from the inside with "Who goes there, by Sky?". The traditional answer was "A friend of Sanctaphrax" and the door would then open, revealing the chief guard. "Enter, friend" would then end the ritual for those waiting on the Mosaic place. The Next-Most High Academe would then walk down the tunnel to inspect the chest of Stormphrax in the Treasury Chamber.
The events influenced the language of Sanctaphrax. "Trust the skies!" had a similar meaning as "Good luck!" and "Librarian's loss!" meant the opposite.
- Belphinius Mendellix, a squire of the Knights Academy
- Hax Vostillix, Hall Master of the Knights Academy
- Maris as an observer and the daughter of the Most-High Academe, Linius Pallitax in The Curse of the Gloamglozer
- Mogworm as the guard of the Treasury Chamber
- Professors of Light and Darkness as Next-Most High Academes
- Quiltis Wistelweb as a squire of the Knights Academy
- Quint as an observer for the first time in The Curse of the Gloamglozer and then as a squire from the Knights Academy in The Winter Knights
- Raffix Emilius, an Upper Hall squire
- Sigbord as the chief guard
- Tonsor Wexis as part of the squires from the Knights Academy
- Vilnix Pompolnius as part of the squires from the Knights Academy
- Welma Thornwood in The Winter Knights
Since treasury Day takes place on the first day of the second moon in its third quarter, it can be celebrated in the real world as well. It usually falls in March, but is sometimes in late February.
Here is a list of Treasury Days from 2015 to 2025:
- 14th March, 2015
- 2nd March, 2016
- 21st March, 2017
- 10th March, 2018
- 27th February, 2019
- 17th March, 2020
- 7th March, 2021
- 24th February, 2022
- 16th March, 2023
- 4th March, 2024
- 23rd March, 2025