The earliest guns were simply tubes, not cast, but built of strips of iron or wood held together by rings. They were breech-loaders, the charge being placed in a loosely-fitting chamber. How the chamber was secured and the gun fired are still undecided. The guns were usually innocent of trunnions and were fastened lengthwise upon wooden beams which could be propped up to give them the desired elevation. It has been recorded that in one of the earliest siege operations at which this primitive artillery was employed, both sides were so interested in the operation of firing that they ceased exchanging missiles and defiance, and even stopped their personal combats, until after the discharge, when, being much relieved that the stone bullet had inflicted no damage on the assailed castle wall and had wounded no one, they resumed hostilities in the old-fashioned way. In those days one discharge per gun per diem was regarded as sufficient. It was customary to load the piece overnight and fire it in the morning, from which it may be surmised that its moral effects were greater than the material destruction caused. Artillery would have to be in a more advanced stage to justify its use at sea, for no vessels could afford to carry guns which could only be used so infrequently. Nevertheless, the moral effects of gunfire were so evident, especially when weapons were made more powerful and able to inflict serious material damage, that the adoption of the new arm for naval war could not be long delayed, and the time soon arrived when both national and private vessels of any size carried one gun or more. By the middle of the fifteenth century guns on board ship had become common. The illustration of the model[14] of a ship of the period 1486-1520 gives a very good idea of what the warships of that time were like. Although the vessel carried guns, the bow and arrow were still relied upon. The archer’s panier on the mast had given place to the deep circular top. Castles, however, were provided fore and aft for the archers, and were useful alike for affording them protection and accommodation and a place of vantage whence to discharge their arrows. The vessel is of the same type as the Spanish caravel of the early sixteenth century. From this it may be inferred that the Spaniards went to the north for the designs of their hulls, but preferred to retain the rig with which they were most familiar, the Spaniards depending largely on lateen yards and sails, whereas the model is square-rigged but without the top-sails she ought to carry. A feature of the sea-going Atlantic vessels of this time was their great beam in proportion to their length. They also had an extraordinary amount of “tumble home,” or sloping of the sides above the water line towards each other. Ships of the type represented by the model were much in advance of those upon which artillery was first carried.