We are given a detailed account of fireballs in the German Firebook, 1400-50, belonging to the Royal Library, Berlin, MS. Germ. qu. 1018. Missiles are there described which consisted of an interior ball of gunpowder kneaded with spirits of wine, smeared over with thick incendiary matter, rolled tightly in a cover of cotton steeped in the same mixture, and secured by two metal bands at right angles to each other. They could be either thrown by hand or fired from a bombard. In the latter case a hole was bored through the ball and the plug which was used in bombards to close the end of the powder-chamber next the projectile, in order to admit the flame into the interior of the ball. The success of the missile, it was thought, depended on the hole through the ball being exactly opposite the hole through the plug, a condition which could be only fulfilled in a breechloading bombard. The inventor believed that the ball would explode, for he warns the gunner to throw it before the flame reaches the composition, lest it “blow his head off.”[570] It is obvious, however, that the gunner’s head was quite safe, although he might burn his fingers, when using these incendiary toys which are unknown to military history. The incendiary projectiles actually used in the fifteenth century were comparatively simple and of a different nature. Take, for instance, the incendiary cannon-projectile used at the siege of Weissenburg in 1469, just six years after Valturio had presented his book to the Sultan Mahomed II.[571] It consisted of a stone ball, considerably smaller than the bore of the gun, which was smeared over with thick incendiary matter and wrapped in a cloth soaked in the same mixture. This process was continued until the ball was the proper size for the bore.[572] Other incendiary missiles were tried,[573] but none of them, so far as I am aware, had anything in common with the unpractical projectile proposed in the Berlin Firebook. _Incendiary Shell._ A further step is taken in a later edition of the Firebook just quoted, but of the same period,[574] 1400-50. A quill full of incendiary matter is directed to be inserted in the hole through the ball above described, and the whole was enclosed in an envelope or shell of earthenware or iron. An earthenware ball could of course only be thrown by hand: an iron ball would be fired in general from a bombard. The metal shell was formed of two hemispheres of iron fastened together by bands, with a small hole to admit the flame to the quill. A similar envelope, of bronze, is suggested by