For one thing, it took both hands to read a scroll properly. Unless the reader was seated at a desk (in which case paperweights or wooden pegs could be used to pin down the springy papyrus), the only way to read a scroll was to unwind it carefully from the right hand and, passing it to the left, to roll it up again. Writers and copyists usually wrote in columns a few inches wide, so that the bulk of the fragile papyrus in the scroll could be kept safely rolled up. Even so, archaeologists have found scrolls whose bottom edges have been worn away where they rubbed against the reader’s clothing.

This, then, was the second major problem with scrolls: papyrus was not an inherently long-lived material, especially if removed from its hot, dry Mediterranean comfort zone. Having taken a liking to a historian who shared his name, Tacitus, emperor from 275 to 276, had to send out new copies of the historian’s works each year to replace those that had rotted away in Gaul and Germania. Papyrus will also crack and tear if it is folded too often, leading naturally to the gently curved shape of the scroll itself – and so to the fact that most scrolls carried writing only on one side. Only if the text on the front of a scroll was no longer needed would its owner flip it over and use the other side; a double-sided scroll was just too difficult to read otherwise.

Shrouded in mystery

Sometime in or before the First Century CE a new kind of book appeared that promised to address the scroll’s shortcomings. The evidence is sparse but telling: archaeologists have discovered a few key scraps of papyrus whose text unexpectedly continues from the front to the back, and whose neat margins one might expect to find in a paged book. And that is exactly what these fragments are: they are leaves from the first paged books the world had ever seen. We know that the Romans called this new kind of book the codex (from caudex or tree trunk, because of its similarity to their wooden writing tablets), but how the codex came to be in the first place is shrouded in mystery. The first written mention of the codex appears in the words of a Roman poet named Martial, who encouraged his readers to buy his books in this new, paged format:

“You who long for my little books to be with you everywhere and want to have companions for a long journey, buy these ones which parchment confines within small pages: give your scroll-cases to the great authors – one hand can hold me.”

Written between 84 and 86 CE, Martial’s sales pitch tells us not only that paged books were known of in the First Century CE but also that some of them, at least, were made from a new material called parchment. This alternative to papyrus, invented in a Greek city-state some centuries earlier, was made from cleaned, stretched animal skins by means of a bloody and labour-intensive process, but its smoothness and strength made it an ideal writing material. Archaeologists have since confirmed Martial’s claims via fragments of parchment codices dated to the First Century – and yet, these few tantalising finds aside, we still know very little about where or why the codex was invented, or who might have done so. Even the question of whether the first codices were made of papyrus or parchment has never been satisfactorily answered.