The new form of armament of ships involved a considerable raising of the height of side, and in order to counteract the effect of the high topside, carrying the weight of guns aloft, the beam of the vessel relatively to its length had to be much increased. The Venetians were, however, afraid to make the transverse section wide throughout, lest the weight of the guns near the sides of the vessel should cause the connection of the sides with the beams to strain; hence they gave the sides considerable "tumble home," or fall inboard, as represented by Fig. 32, which shows the cross-section of a Venetian galleon. It will be noticed that the width of the upper deck is only about half that of the greatest beam. This practice was afterwards carried to an absurd extent by the Venetians and their imitators, even in cases where guns were not carried aloft, as may be seen from the sketch of a galleon given in Fig. 33. Hence it is evident that the introduction of ordnance on board ship accounted for a complete revolution in the proportions of hulls hitherto in vogue. The rig of ships also underwent a considerable development about this period. The old single mast of the galley was supplemented by two and in some cases by three others. The sails were still square sails carried on spars, and the practice of reefing the sails to the spars aloft, instead of lowering spars and sails together on deck, had now become common. [Illustration: FIG. 32.--Cross-section of a Venetian galleon.] Two years after the action off La Rochelle we find the French commencing the construction of a Royal Navy at Rouen. This step was taken in consequence of the strong opinion held by Jean de Vienne, who was appointed Admiral of France in 1373, that vessels built specially for the purposes of war would have a great advantage over the hired merchantmen which had to be adapted for fighting each time they were impressed.