The employment of gunpowder in warfare robbed the knight of the protection which he had previously enjoyed from the wearing of metal armor, and thenceforward his life was as much imperiled in battle as was that of the foot-soldier, who was not permitted to protect his person in this manner. Thus were the two upper classes of the community, the nobles and the bourgeois, in any conflict which might arise between them, placed more nearly upon a footing of equality. The ultimate result showed itself in an increased importance, an increased prosperity, of the middle class or _bourgeoisie_, from which the physicians chiefly came. Indeed, feudalism from this time forward rapidly ceased to exist. The discovery of paper, an excellent and relatively cheap substitute for parchment, facilitated wonderfully the spread of knowledge. Parchment, the material upon which books were written, was expensive and was at times difficult to obtain; both of which circumstances rendered books so costly that only a few physicians were able to become the owners of the important standard medical works of that period--such, for example, as the Hippocratic writings, Galen’s treatises, the surgical manuals of de Mondeville and Guy de Chauliac, the pharmacopoeia of Dioscorides, and still other books of lesser value. And, if a satisfactory method of manufacturing paper had not first been discovered, the benefits growing out of the invention of printing in 1467 would have been far less than they actually proved to be. Some idea of the magnitude of these benefits may be formed from the following statement of facts. The demand for books, after the invention of printing, became so great that the presses were kept almost constantly busy. At first, according to the record furnished by Haeser, Venice and Rome took the lead in supplying this great demand for books; the former city printing 2978 and the latter 972 volumes between the years 1467 and 1560; but, during a later period (1500–1536), Paris outstripped Venice with a total of 3056 volumes, and Strassburg advanced to the second place with a showing of 1021 volumes printed during the same period of time. Thanks to the great diminution in the market price of books that resulted from the two inventions named--the manufacture of paper and the introduction of printing--almost every physician in fairly prosperous circumstances was able at that period to purchase the relatively few medical treatises which issued from the presses; and, besides, new authors were thenceforth stimulated to put their experiences into print. Among the very first medical books printed the following deserve to be mentioned:-- (In Germany.) _Buch der Bündth-Erznei_, by Heinrich von Volsprundt, 1460.--_Das buch der wund Artzeny. Handwirckung der Cirurgia von Jyeronimo brunschwick_, 1508.--_Das Feldtbuch der Wundtartzney_, by Hans von Gerssdorff, 1517.