The transformation of the medieval European image of the world in the period following the Great Discoveries of the 15th and 16th centuries is the subject of this volume. The first studies deal specifically with the emergence of the concept of the terraqueous globe. In the following pieces Dr Randles looks at the advances in Portuguese navigation and cartography that helped sailors overcome the obstacles to the circumnavigation of Africa and the crossing of the Atlantic, and at the impact of the Discoveries on European culture and science. Other articles are concerned with Portuguese naval artillery, and with attempts to classify the indigenous societies of the newly-discovered lands and to map the interior of Africa.

From the early Christian era and throughout the Middle Ages, theologians exerted considerable effort to achieve a synthesis bringing together Greek cosmology and the Creation story in Genesis. In the construction of the medieval Empyrean, the dwelling place of the Blessed, Aristotle's philosophy proved of critical importance. From the Renaissance on, largely in revolt against Aristotle, humanist Bible critics, Protestant reformers and astronomers set themselves to challenge the medieval synthesis. especially effective in the ensuing dismantlement, from the 16th to the 18th centuries, was the pagan concept of an infinite universe, resuscitated from Antiquity by the Italian philosophers Bruno and Patrizi. Indirectly inspired by the latter, the doctrines of the French pre-Enlightment thinkers Descartes and Gassendi spread throughout Latin Catholic Europe in spite of considerable resistance. By the middle of the 18th century the Roman ecclesiastical authorities were brought to acknowledge an end to the medieval cosmos, allowing catholics to teach the theory of heliocentrism.