~Holmes~ reproduces, besides, the ships which figure on an old Bayeux tapestry (1066), as well as the “Sandwich Seal” of 1238, the “Dover Seal” of 1284 and the “Pool Seal” of 1325 (pp. 67 and 68). These three seals agree with the oldest of the arms of Amsterdam and the ship which they carry is, in every respect, similar to that of the said city. Too much importance cannot be attached, however, to this detail, because, just as the lion of heraldry is very little like a real lion, it is to be supposed that the heraldic ship is not a faithful reproduction of the real type. The old illustrated Bible of 1200-1220, preserved in the Royal Library of The Hague, and which seems to have come from Northern France, contains also a remarkable reproduction; the type of boat which it gives is also like the preceding ones. [Sidenote: II 112] The identity of all these figures allows it to be supposed that a single type of ship ruled in Western Europe; while the clearly pointed out timbers of the planking shows clinker built work. [Sidenote: II 78] The reproduction of the Bayeux tapestry shows, besides, that the sail was very early in use; the pilot of one of the ships shown there holds the sheet in his hand. Besides--and this fact is worthy of notice--these vessels all have sensibly vertical stems and sternposts, just as they are still found in our times on a few Norwegian fishing boats. The “cog”, the vessel in the arms of Amsterdam, is a very well known mediæval type, of which the importance becomes marked in Western and Central Europe from and after the XIIIth century, when the Hanse towns and the Frisians improved it greatly. This ship, which was very broad for its length, was hard to board, whence its usefulness in time of war. The “cog” seems to date back further than the institution of the Hanseatic league (1250) judging by the fact that its name was known well before this date. Thus, the inhabitants of the Netherlands had to equip several cogs wherewith to fight the invasions of the Norsemen (810-1010). It was the application of the feudal system to navigation. (See ~La Croix~, p. 88.) It is known that this policy was finally established under Charlemagne who subjugated the Frisians in 785 and the Saxons in 804. (Mr. ~J. C. de Jonge~, _History of the Navy of the Netherlands_, Vol. 1, p. 6.) It is needless to say that everything was soon put to work to escape it. A charter of the Roman King Otho I (936-973) calls for a tenth of a “cog” (Kogschult) of which the product came to the bishop of Utrecht. It was the commutation for the obligation to serve the prince with cogs. This obligation seems, in principle, to have struck more especially the countries lying along the present Zuyder Zee. (Mr. ~de Jonge~, Vol. I, p. 7.) The “cog” only appears for the first time in Germany in 1211, when the Emperor Otho IV allowed the inhabitants of Wismar to maintain two “cogs” (Cogken), and as many small vessels as they desired.