A colorfully illustrated biography of the Greek philosopher and scientist Eratosthenes, who compiled the first geography book and accurately measured the globe's circumference.

How do you measure the size of the planet you're standing on? "Circumference" is the story of what happened when one man asked himself that very question. Nicholas Nicastro brings to life one of history's greatest experiments when an ancient Greek named Eratosthenes first accurately determined the distance around the spherical earth. In this fascinating narrative history, Nicastro takes a look at a deceptively simple but stunning achievement made by one man, millennia ago, with only the simplest of materials at his disposal. How was he able to measure the land at a time when distance was more a matter of a shrug and a guess at the time spent on a donkey's back? How could he be so confident in the assumptions that underlay his calculations: that the earth was round and the sun so far away that its rays struck the ground in parallel lines? Was it luck or pure scientific genius? Nicastro brings readers on a trip into a long-vanished world that prefigured modernity in many ways, where neither Eratosthenes' reputation, nor the validity of his method, nor his leadership of the Great Library of Alexandria were enough to convince all his contemporaries about the dimensions of the earth. Eratosthenes' results were debated for centuries until he was ultimately vindicated almost 2000 years later, during the great voyages of exploration. "Circumference" is a compelling scientific detective story that transports readers back to a time when humans had no idea how big their world was--and the fate of a man who dared to measure the incomprehensible.

This is the first modern edition and first English translation of one of the earliest and most important works in the history of geography, the third-century Geographika of Eratosthenes. In this work, which for the first time described the geography of the entire inhabited world as it was then known, Eratosthenes of Kyrene (ca. 285-205 BC) invented the discipline of geography as we understand it. A polymath who served as librarian at Alexandria and tutor to the future King Ptolemy IV, Eratosthenes created the terminology of geography, probably including the word geographia itself. Building on his previous work, in which he determined the size and shape of the earth, Eratosthenes in the Geographika created a grid of parallels and meridians that linked together every place in the world: for the first time one could figure out the relationship and distance between remote localities, such as northwest Africa and the Caspian Sea. The Geographika also identified some four hundred places, more than ever before, from Thoule (probably Iceland) to Taprobane (Sri Lanka), and from well down the coast of Africa to Central Asia. This is the first collation of the more than 150 fragments of the Geographika in more than a century. Each fragment is accompanied by an English translation, a summary, and commentary. Duane W. Roller provides a rich background, including a history of the text and its reception, a biography of Eratosthenes, and a comprehensive account of ancient Greek geographical thought and of Eratosthenes' pioneering contribution to it. This edition also includes maps that show all of the known places named in the Geographika, appendixes, a bibliography, and indexes.

"This fantastical picture book, like its hero, is bursting at the seams with creativity. . . . a vigorous shot in the arm to nonconformists everywhere" — Publishers Weekly (starred review) Enter the witty, intriguing world of Weslandia! Now that school is over, Wesley needs a summer project. He’s learned that each civilization needs a staple food crop, so he decides to sow a garden and start his own — civilization, that is. He turns over a plot of earth, and plants begin to grow. They soon tower above him and bear a curious-looking fruit. As Wesley experiments, he finds that the plant will provide food, clothing, shelter, and even recreation. It isn’t long before his neighbors and classmates develop more than an idle curiosity about Wesley — and exactly how he is spending his summer vacation.

Contains 250 questions and answers about astronomy, particular for the amateur astronomer.

Weights and measures form an essential part of our ingrained view of the world. It is just about impossible to function effectively without some internalized system of measurement. In this volume, I outline a history of the science of measurement, and the