Okay, let's go with:

Iron Wrought and Iron New

A thorough technical discussion on the merits and chemical attributes of iron, including a map that illustrates ore-heavy mountains both within the Ke-Sanwon region and globally. Instructions on how to achieve common alloys, which local metals best bind with iron, the most efficient local tools to utilise, and a few recipes to forge bolts, cutlery, coarse swords. A good starter's guide on mining, cleansing, working with and forging iron.

Follows the spread of pox and fever sicknesses across the (now-severed) eastern continent, including a majority of old folks' tales and superstitious cures, and moving into medical healing. Covers a variety of largely extinct illnesses and documents their anecdotal impact on local culture and politics. Small incursions into poisons, typically when the lethal ingredient was organically found commonplace across a region and obliviously ingested by the local populace (leading to addictions to a brand of light opiates, indigestions or poison because of local mushrooms, etc). The focus of the book is ultimately historical — this is not a thorough medical text.

Physical thermodynamics, with some incursions into magical application. Examples range from water and hydrogen (known here as the lung coils) to obscure chemicals unique to the world of Akhuras. The inevitable section on volcanos details the states of lava. The book includes several theoretical and mathematical exercises, some of which past readers have solved with the appropriate formulas on the edges or corners of some pages.

A history of evolving sentience among fish kind, culminating in the appearance of mermaids. Deep detail on the politics, mating and migration patterns and feeding rites of various tribes. Specifies where mermaids can be encountered. Details how some became extinct, while others thrived. Includes a clearly repeatedly read chapter on whether there is merit to the tales of romance kindled between mermaids and humans (the author posits that these stories must have originated because of sailors' interactions with the highly social mermaids of the now defunct Lessardus tribe; the author further believes landlocked individuals projected their own behaviours onto mermaids — aka, misunderstood the errant twitches of their facial muscles as 'smiling.')

A visibly newer, original manuscript written in ink. The story of Master Moon, who descended from the heavens, incensed that he winked at the earth, and the red eye of a mountain winked back with impunity. He crossed lands to reach this mountain, swearing to stab its eye shut. On his way, Master Moon started to know the people of the realms, and their strange devotion to their mountain. As he got closer to the mountain's lid, he met three knights who opposed him, defeating each: one with a riddle, another at drink, the third in combat. Finally, reaching the edge of the mountain, he called for the eye within to meet him in contest or battle. But the mountain refused him, and Master Moon called on every one of its ancestors to come witness the mountain's cowardice, shaming it. And the more spirits of the elders gathered, the more they ridiculed the mountain, and the more the mountain's eye whittled shut. Until Master Moon was content once more, and he flew back into the heavens, as every elder stood up, cried and clapped.