The use of iron and lead balls, the superiority of which over balls of stone had doubtless been manifested in former centuries in connection with the projection of Greek fire, was practised by the Florentines soon after the invention of guns themselves. The discovery of “corned” gunpowder took place a century later. In its original form gunpowder possessed many disadvantages as a propellant. Ground into a fine powder, and composed in the first instance of almost equal proportions of saltpetre, sulphur, and charcoal, it was peculiarly liable to accidental explosion, so that frequently the charcoal was kept separate from the other ingredients and mixed just prior to use. If kept mixed it easily disintegrated, in the shaking of transport, into three strata, the charcoal coming to the top and the sulphur sinking to the bottom. It was intensely hygroscopic, and quickly fouled the barrels of the pieces in which it was used. But, most important of all, the efficiency of its combustion depended to an inconvenient degree upon the density with which, after being ladled into the gun, it was rammed home. The greatest care had to be exercised in ramming. If pressed into too dense a mass the powder largely lost its explosive character; the flame which ignited the portion nearest the vent could not spread through the mass with sufficient speed; it quietly petered out. If rammed too loosely, on the other hand, the explosive effect was also lost. A great gain ensued therefore when, in place of the fine or “serpentine” powder, corned powder came to be used, about the middle of the fifteenth century. In this form the powder was damped and worked into grains, crushed to the requisite size and sieved for uniformity. These grains were finally glazed to prevent deterioration from the effects of damp; and the resulting powder proved stronger and more efficient in every way than the same mixture in its more primitive form. Some time was to elapse before guns could be cast of sufficient strength to withstand the force of corned powder. “Chemistry had outrun metallurgy.” The larger species of ordnance were restricted to the use of serpentine powder until the middle of the sixteenth century. Nevertheless, cast ordnance as well as the lighter forged iron guns were developed continuously for service in the field. Named after birds and reptiles and clumsily cast of such shapes and weights as pleased the founders’ fancy, they were of use chiefly in demolishing by attrition the gates and walls of forts and cities. From the battle of Cressy onward, first in huge carts and then on their own wheeled carriages, they rumble across the pages of European history. §