Many things tended to bring about the art of the Renaissance. The great impulse given to learning by the study of the writings of the Greek and Roman poets, lawyers, and philosophers, and the keen study of the rich legacy of art and architecture left by Greece and Rome, may be reckoned among the chief causes which led to the development during the fifteenth and sixteenth centuries of the Re-Birth or Renaissance both of literature and art. Dante, and his successors Petrarch and Boccaccio, were called “Humanists,” for the reason that they studied and advocated the knowledge that was needful to man in his progress and in relation to his life in this world, and did not confine themselves wholly to theology, which was the case with those who devoted themselves to learning in the Middle Ages. This led to a wider spread of knowledge among the people, which was greatly stimulated by the invention of printing. The rulers of the people also encouraged learning and promoted the arts to an extent unknown before. In Florence, especially, under the powerful and beneficent rule of the Medici family, art and literature received every attention, and made rapid progress in every department of cultured knowledge and skilful handicraft. Great artists like Niccola Pisano, Brunellesco, Donatello, Giotto, Alberti, and others of the early period, whose individuality and great personality did more than anything else to bring about the epoch and the art of the Renaissance, studied with evident purpose the existing remains of the art of Ancient Rome. In this they only followed the movement of the day in every branch of art and learning: all classes in every walk of life were then directing their footsteps to Rome in the pursuit of knowledge. About the year 1414 the discovery was made in the Monastery of St. Gall of the celebrated codex of Vitruvius, a work wherein the learned writer had set forth the principles of Roman architecture of the Augustan era. This work was reprinted later at Rome, and was very much used by architects as a guide for the better understanding of the Roman temples and other buildings. As the Gothic style in France, Germany, and in England was approaching its climax, the art of the Renaissance in Italy was developing, and the period of decadence in the former was contemporaneous with the finest period of the latter—towards the end of the fifteenth century. The transition, or early beginnings of the Renaissance, has been called the Trecento (1300) style, which in its ornamental features is characterised by a free use of conventional foliage, mixed with Saracenic or with Byzantine ornament, interlacings, and scroll work; in sculpture and painting by a closer study of nature and of antique remains, with an endeavour to shake off the former stiff Byzantine traditions; and in architecture by the use of the round arch and a revival of some other features of the classic orders. Niccola Pisano, Arnolfo di Lapo, Orcagna, and Giotto