And to that same place, he added, the stream carried all that was caught in its current—like the spar and plank floating near us, so that the sea was covered with a thick tangle of the weed in which were held fast fragments of wreckage and stuff washed overboard and logs adrift from far southern shores, until in its central part the mass was so dense that no ship could sail through it nor could a steamer traverse it because of the fouling of her screws.[39]
He admits this theory of formation was inaccurate but later refers to “the dense wreck-filled center of the Sargasso Sea” and makes his castaway hero declare:
What I looked at was the host of wrecked ships, the dross of wave and tempest which through four centuries has been gathering slowly and still more slowly wasting in the central fastnesses of the Sargasso Sea.[40]
Sir John Murray naturally gives a more moderate and scientific account, explaining:
The famous Gulf Weed characteristic of the Sargasso Sea in the North Atlantic belongs to the brown algae. It is named Sargassum bacciferum, and is easily recognized by its small berry-like bladders.... It is supposed that the older patches gradually lose their power of floating, and perish by sinking in deep water.... The floating masses of Gulf Weed are believed to be continually replenished by additional supplies torn from the coasts by waves and carried by currents until they accumulate in the great Atlantic whirl which surrounds the Sargasso Sea. They become covered with white patches of polyzoa and serpulae, and quite a large number of other animals (small fishes, crabs, prawns, molluscs, etc.) live on these masses of weed in the Sargasso Sea, all exhibiting remarkable adaptive coloring, although none of them belong properly to the open ocean.[41]
Finally we have from the Hydrographic Office the official naval and scientific statement of the case. In the little treatise already referred to, Lieutenant Soley tells us that the southeast branch of the Gulf Stream “runs in the direction of the Azores, where it is deflected by the cold upwelling stream from the north and runs into the center of the Atlantic Basin, where it is lost in the dead water of the Sargasso Sea.”[42] As to just what this is the office answers:
Through the dynamical forces arising from the earth’s rotation which cause moving masses in the northern hemisphere to be deflected toward the right-hand side of their path, the algae that are borne by the Gulf Stream from the tropical seas find their way toward the inner edge of the circulatory drift which moves in a clockwise direction around the central part of the North Atlantic Ocean. In this central part the flow of the surface waters is not steady in any direction, and hence the floating seaweed tends to accumulate there. This accumulation is perhaps most observable in the triangular region marked out by the Azores, the Canaries and the Cape Verde Islands, but much seaweed is also found to the westward of the middle part of this region in an elongated area extending to the 70th meridian.
The abundance of seaweed in the Sargasso Sea fluctuates much with the variation of the agencies which account for its presence, but this Office does not possess any authentic records to show that it has ever materially impeded vessels.[43]
Perhaps these statements are influenced by present or recent conditions. It is obvious that giant ropelike seaweeds in masses would more than materially impede the action of the galley oars, which were the main reliance in time of calm of the ancient and medieval navigators. Also it is hardly to be believed that small sailing vessels could freely drive through them with an ordinary wind. If the weeds were so unobstructive, why all these complaints and warnings out of remote centuries? In the days of powerful steamships and when the skippers of sailing vessels have learned what area of sea it is best to avoid, there may well be a lack of formal reports of impediment; but it certainly looks as though there were some basis for the long established ill repute of the Sargasso Sea.