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Aft of the mainmast mortise and on either side of the step are two carved-out pump shaft receptacles, each approximately 32 cm in radius, leading into the bilge. Since every wooden ship leaks, especially at sea, functional pumps (bombas) to clear water from the lower hull are a critical part of seafaring and require constant attention and care. The pump sumps extend between two floors to the garboard strake, and are situated 30 cm abaft the mainmast mortise. Only the port sump was excavated; the starboard was left undisturbed. Width of the mast step between the two sumps measures 23 cm. Each sump once held a pump shaft (mangueta), fashioned from the hollowed-out trunks of trees to form a tube. Water in the bilge was manually forced up the shafts by various types of piston rods and valves to the main deck, where it was allowed to run overboard. Pumping the bilge (achicar la bomba) was a routine chore aboard a ship; on older vessels continual leakage had to be monitored carefully for the sake of cargo below and the safety of the ship. Crewmen on the first daylight watch took a keen interest in the color of water coming up from the bilge. If it was dark and foul, they were glad; if it was clear and green, they began to worry.
A similar dual pump arrangement was recorded on another Basque galleon found near San Juan in Red Bay, Labrador (Grenier 1988:76, Fig. 14), while San Juan only had one pump. The early 16th-century Spanish wreck at Highborn Cay, Bahamas had two pump sumps; however, both were situated on the port side of the step, and the aftermost one appeared to be unfinished, or aborted (Smith 1993:71). To improve safety at sea, one of the many maritime edicts of Philip II required in 1552 that newly-constructed ships were to have two pumps (Casado Soto 1991:99). Enforcement of this requirement may have taken time to become widespread. Unlike the single pump sump in San Juan, which was found to be rather crudely fashioned (Waddell 1985: 257), the sumps in the Emanuel Point Ship appear to have been carefully carved with forethought and finished with care.
Although no remnants of pump shafts or hardware were found, a small square board, 21 cm in length, 18.5 cm in width, and 2 cm in thickness, with a nail at each corner, was discovered lying on the garboard strake. This board may have provided a bed on which a pump foot valve (morterete) rested. A similar board was found in the bilge of the Fuxa wreck in Cuba, thought to be Nuestra Señora del Rosario, which ran aground in 1590. It displayed a distinctive circular impression of the foot valve base on one side ( Smith 1993, pers. comm.; Lopez, Perez 1993). The lack of pressure marks on the Emanuel Point board suggests that perhaps the pump tube rested not on the board against the hull, but rather was braced on the exposed floors on either side of the pump shaft (Oertling 1993, pers. comm.; Lopez, Perez 1993). A smaller section of the tube, around 22 cm in diameter, could have extended the pump bore into the sump and onto the valve and its board. Arranged in this fashion, stress created by downward tube pressure would have been taken by the floors, instead of the board.
To protect pump sumps from becoming clogged by ballast stones or bilge debris, a pump well (arca), or wooden enclosure, was constructed around the pump shafts. Several disarticulated structural remnants discovered around the sump probably represent baseboards from the pump well. One baseboard remnant, lying to port and parallel with the pump sump, was found in place; a portion of it extended over the buttresses and bilge boards. Others were not sufficiently preserved to reconstruct the architectural features of the pump well. As mentioned above, the small mortise at the transition from the step to the keelson may have housed a pump well framing timber.
Fig. 11. Overhead view of the port pump sump. Note two timbers at right and center that may represent remnants of the pump well structure.
Fig. 12. The pump shaft was housed in the pump sump to clear water from the bilge.