Writing The Viper Amulet sent me on an Internet voyage to discover how first-century travelers managed to navigate their way around the Mediterranean Sea… a water-world of islands, inlets, rocks, shoals, and sandbars surrounded by—and occasionally interspersed with—chunks of terra firma. Many ancient ships sank in the Mediterranean, so sailing must have been an immensely dangerous endeavor.

The information I turned up was fascinating, but putting it to good novelistic use required imagination and shrewd powers of deduction. Fortunately, I have plenty of each!

I learned that there was little dependable navigational guidance available until late in the life of Emperor Claudius (10 B.C. – 54 A.D., which ended a year after Rubies of the Viper begins). Sailors apparently followed the coastlines as closely as they safely could. Venturing without modern aids across the biggest body of water in their known world must have taken great courage.

In 43 A.D., Pomponius Mela, an Iberian geographer living in Rome, “published” a short book (ie, a scroll) describing in words a bare-bones outline of the Mediterranean Sea. He had access to some older sources, mostly Greek texts, which he combined and elaborated on. Logically, for someone born in southern Spain, his description begins with the Straights of Gibraltar; moves east along the north-African coast, northeast along Judea and Syria, and north to the Black Sea. Eventually, his description makes its way around Greece and Italy and winds up back in Spain.

Other than their general shapes, Mela did not describe the land masses surrounding the Mediterranean. Places whose size and shape were generally unknown at the time (eg, Africa) are greatly reduced from what we moderns know to be their actual size.

If you’d like to see a graphic portrayal of Pomponius Mela’s vision of the world, click here.

So… Pomponius Mela provided an overall geographical description of the Mediterranean. But how did all that verbiage translate into something useful for naval captains and ordinary sailors and fishermen, most of whom must have been illiterate and none of whom would have possessed a one-of-a-kind manuscript?

Here’s where my powers of deduction come in.

Pomponius Mela’s geographical description certainly made it into the hands of Emperor Claudius, a scholar who would have appreciated the work and realized the value of this new information. (In fact, getting it to Claudius was probably the reason Mela wrote his book in the first place. It’s a safe guess that he—like so many other foreigners in the imperial capital—was ambitious to get a good appointment in the palace.)

In writing The Viper Amulet, I’ve made the assumption that Claudius would have encouraged somebody in the palace, perhaps even Mela himself, to accept the task of developing a visual rendition of this verbal description… to put it into a format that could be more easily used. In modern words: to create a map.

It wouldn’t have been called a map in those days, of course.

The best term that my adviser on all things classical has suggested to describe this wondrous first-century creation is: a drawing on parchment. So, in The Viper Amulet, my characters have the benefit of a new-fangled “drawing on parchment.”

My characters wouldn’t have had the original drawing, of course. No doubt that was safely kept in the imperial palace in Rome, a fact that could have continued to make life difficult for those sailing the Mediterranean. So—again using those powers of deduction—I assume that hand-made copies of the original “drawing on parchment” would have been distributed to Roman Navy captains. Subsequently, one can envision the many generations of copies—copies of copies of copies—that would have been produced, in all probability becoming less and less accurate, but still better than nothing at all.

To my mind, this is a logical series of steps… starting from the historical reality of Pomponius Mela’s written description and imagining the development of graphic representations that would have helped all who could get their hands on them. I can’t prove that my characters obtained travel assistance in exactly this way, but the “copies of copies” that they manage to find in Sicily surely would have been a big help to anyone in their situation.

—text copyright © Martha Marks—