All these decades and books later, there’s still so much to know. I recently encountered Majd ad-Din Usama ibn Murshid ibn Ali ibn Munqidh al-Kinani, aka Usama, a Syrian nobleman, diplomat and faris, or knight, who authored the incredible “Book of Contemplation” in the 1180s, and the librarian Mohammed Al-Khwarizmi, who’s better known for introducing algebra, Arabic numerals to Europe and camel milk, because good books are like powerful rivers, flowing not towards dead-ends, but deltas of possibilities.

Take for example “The Crusades: the Authoritative History of the War for the Holy Land” by Thomas Asbridge. It’s “a truly comprehensive history of holy war in the Holy Land,” according to Publisher’s Weekly, that “reads like an adventure story, albeit one that is both factual and informative.” The 12th century was a grim time, especially among the “Franks,” as the Moslems called everyone from Western and Central Europe. Consider Pope Urban’s call to arms at a gathering of thousands of nobles, knights, and priests at Clermont, France, in 1095. As Larry Gornick’s reliable “Cartoon History of the Universe Vol. III” reminds us, “What about the smell? It must have been something, since the Franks rarely bathed in those days! The pope called on the reeking crowd to carry the war to Jerusalem … 30 thousand mouths full of decaying teeth bellowed back.”

The guardian.com reviewer called Asbridge’s history “a grueling book … But for those who have the stomach, Asbridge’s lengthy narrative builds into a haunting and thought-provoking story.” Sure enough, but it mentions Usama’s “Book of Contemplation,” his autobiographical memoirs describing events from the first crusade to Saladin’s reconquest of Jerusalem and courtly life from a Syrian nobleman’s perspective. Warrior, poet, advisor to the mighty, and accomplished schemer, Usama lived to 93, despite personally fighting in 15 major battles — only two of which involved crusaders — and instigating a series of assassinations in Egypt. Usama was best known in his lifetime as an “adib,” or man of letters, and one of his greatest personal disasters came when crusaders pillaged his library.

Al-Khwarizimi, another bookman, was named head of Baghdad’s House of Wisdom, then the greatest library in the world, in 820. He also wrote “Hisab al-Jabr wa-al-Muqabala,” the greatest mathematical work of the age, from whence Europeans acquired the term “algebra” as well as the concept. He also described Arabic numerals, which were actually invented in India between 100-400, in terms of angles. Numeral one is an upright line with a small cap, rendering one angle. Two was Z-shaped, with two angles, three was the capital Greek letter “sigma” but backwards, and so on.

Many people find library decimal systems daunting. Many intelligent applicants fail our public library’s shelving exam after forgetting that in decimal-land .274 is smaller than and comes before .2. A pal recently asked why our public library uses the Library of Congress decimal system that begins with letters instead of the more famous Dewey Decimal System. Despite being branded with a “C” in cataloging in library school — suffice to say my son was born the day of the final exam — bibliofiend Terrence Cole once gave me an 1899 edition of Dewey’s “Classification and Index,” and I demonstrated how Dewey’s 10 basic subjects (philosophy, religion, sociology, philology, natural science, useful arts, fine arts, literature, history and “general works”) are more confining than the 21 letters used by the Library of Congress (I, O, W, X and Y are reserved for future unknown categories) that are then followed by decimals like Dewey’s. For example, the LC number for “New Middle Eastern Street Food” a cookbook from our library, begins TX725.M628, with “TX” meaning “home economics, “725” standing for “modern cookbooks,” and M628 for “Middle Eastern, Australian and African cooking.”

So camel milk, which is three times higher in vitamin C and 10 times higher in iron than cow’s milk and lower in cholesterol and lactose (and costs 50 times more since they mature and gestate more slowly), falls in the TX725 section, too. Good books provide plenty for me to write about, and as H.L. Mencken said, “I write in order to attain that feeling of tension relieved and function achieved which a cow enjoys on giving milk.”

Greg Hill is the former director of Fairbanks North Star Borough libraries. Contact him at 479-4344.