The Magician's Library

A good magical library has books covering a variety of subjects, many of which may be concealed or coded or only tangentially related to magic. It would look something like a philosopher's library crossed with a science reference library.

Example books or sections might include:

• A history of local rocks, with a second section on how those rocks are formed. Notes in the margins are copied from tables of densities and chemical makeups, as well as the outlines of spells like stone shape and passwall.

• A technical journal filled with common calculations & numbers so a mage doesn't have to do them on the fly: pages and pages of logs, tangents, triangles, conversions, curves, and the like (like an engineer's workbook).

• A collection of children's stories from several centuries ago, with an older translation and a newer translation. Five out of the six seem to contain or center on a specific town filled with talking animals beset by a kind of devil fox. A note in the back has several stabs at its true name.

• A biography of a powerful cleric detailing his rise and fall, and his friend the mage, about whom few histories survive.

• A collection of letters penned between a noblewoman in the capitol and her sister in the country, a snapshot of a moment in the nation.

• A book of alchemical projects for beginners, such as stain remover, laden jars, how to construct a simple workbench, and basics of safety (fire control, eye protection, common noxious gas mixtures, etc.).

• A sheaf of patterns for a tailor to make robes, stoles, girdles, leggings, broad-brimmed hats, and etc. - all the wizardly classics.

• A text all in purple prose by an author with a ridiculous name telling one how to 'propitiate the celestial bodies and unlock your inner power' or some such nonsense, clearly bunk to any serious practitioner. However, the symbolism matches almost identically to several powerful illusion spells, and with a bit of work a good wizard could tease out the fundamentals of seeming or hallucinatory terrain.