478 THE POPULAR SCIENCE MONTHLY. 



which Europe derived from the Crusades. The armies were intent 

 upon booty and power ; the philosophers who followed them were 

 seeking for new truths ; and the advance of knowledge that they re- 

 turned with is one of the benefits the West of Europe derived from 

 the Crusades. 



Let us note some of the most important prizes they carried home. 

 At Amalfi, a port in the southern part of Italy, a stopping-place for 

 the Crusaders, they discovered a copy of the " Institutes and Pandects 

 of Roman Law," a work which had been long lost to the world. From 

 the Arabians of Spain or Alexandria they procured the works of Plato 

 and Aristotle, as well as other learned treatises of ancient sages. These 

 they studied and commented on with assiduity, each one according to 

 the bent of his mind. Hence, in time we find the learned men not 

 only becoming numerous, but divided into classes. Some follow the 

 study of religion, humanity, and mind ; others devote themselves to 

 history, grammar, and poetry ; others to law ; others to mathematics 

 and astronomy, and others to architecture. But we must keep in view 

 that all these sciences and arts were yet in a crude state, far, far be- 

 neath what they are at this day. The book-men, the theorists, the 

 philosophers, had centuries of research, discussion, and reflection to 

 accomplish, and numberless labors to undergo, before producing the 

 good harvest we are now enjoying. 



Thus, in the thirteenth century the book-men and their disciples, 

 the lawyers, politicians, poets, painters, masons, astronomers, architects, 

 navigators, physicians, and all other seekers and distributors of knowl- 

 edge, had hosts of adherents among the masses. Hence, the practical 

 results of the labors of the scholars were becoming more apparent. 



In religion St. Thomas produces his " Sum of Theology," and brings 

 the scholastic philosophy to its perfection. In politics, the yeomanry 

 of England, instigated by Archbishop Langton, a book-man, demand 

 and obtain Magna Charta that is to say, no taxes without repre- 

 sentation, trial by jury, habeas corjnis, and no taxes without the con- 

 sent of Parliament ; while in Florence a democratic constitution is 

 established by the people. In science, the labors of the alchemists 

 and astrologers are progressing toward the first positive dawn of 

 chemistry and astronomy ; and Roger Bacon, the first of the great 

 prophets of natural science, reveals some of the most important secrets 

 of chemistry. Roger Bacon, the first of the natural philosophers, who 

 was he ? "History answers a book-man, a monk, a solitary student of 

 the works of his predecessors in philosophy and theology. In the arts, 

 Gothic architecture raises a worthy tribute to Heaven. We also find 

 that in this century navigation begins to improve and commerce to be 

 developed, particularly in England and in Italy ; and the learned take 

 advantage of the facilities thus afforded to undertake voyages in search 

 of geographical and other knowledge. Among the rest, Marco Polo, 

 a student of languages, travels throughout Asia, finds his way even to 



