In a world where the sea is a sentient, often malevolent, entity, a chart is more than a map. It is a prayer, a weapon, and the only prayer that offers a truthful reply. For the Arunean Navy, the repository for this sacred knowledge is not a simple collection of scrolls, but a masterpiece of grim, practical artistry: the Rhumb Atlas. This week, I’m opening my sketchbook to share the design and the deep, in-world lore behind this crucial artifact from The Reply.
The Rhumb Atlas is more than a tool; it is a navigator’s bible, a tangible symbol of a maritime nation’s soul. The Arunean Admiralty Atlas, the primary version, is a massive portfolio bound in water-resistant Hammersheer-hide and reinforced with polished brass. Its construction is the purview of Theastone’s legendary Chart-Wright Guilds, with designs ranging from the starkly functional to the grandly bespoke. Each atlas secures the permanent, master charts of the known world—a library of hard-won, generational knowledge.
To secure such a priceless object on a rolling ship, it is kept not on a simple shelf, but on a dedicated chart bar or more complex Navigator’s Arcing Rack. On frigates like the Siren’s Reply, this is a masterpiece of compact engineering: a sophisticated, counter-weighted brass arm that rises from a hidden channel within the great chart table itself, allowing the entire Atlas to be swung into place for use, its weight always secure in a perfect fusion of artistry and grim, practical necessity.
The true genius of the Atlas, however, is its internal mechanism. The vellum charts are not simply bound, but are held taut by a series of spring-loaded brass bars. A simple press of a release catch allows a navigator to remove or insert a single Rhumb Chart in seconds, transforming a vast library into a functional, single-page workspace. This elegant piece of engineering allows for both secure storage and immediate, practical use in the heart of a storm.
But the Admiralty Atlas, for all its authority, does not tell the whole story. The most dangerous voyages are not charted with its permanent, sacred ink, but with the ephemeral, secret lines of a Factor’s Folio. These slimmer, more utilitarian leather portfolios contain the high-value, high-risk intelligence commissioned by a Lord Factor for a specific voyage. Due to the shifting, sentient nature of the Oraen, the accuracy of these charts is guaranteed for only a short period, typically a three-month sanction.
When a Factor’s chart “goes cold,” it becomes a liability. By the harsh laws of the Trading Companies, it must be committed to the flames in a grim ritual, ensuring a rival never captures its secrets. This constant cycle of creation and destruction is a quiet, constant reminder to every sailor of the fleeting, dangerous nature of the sea’s truths.
Fair winds,
—D.S. Black
This is such an intricate, beautiful piece of engineering. Your attention to detail in worldbuilding is absolutely incredible - I keep falling in love with it over and over again any time you introduce something new. It's so precious to me.