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Excavations between the ballast mound and a partially exposed gudgeon (the female part of the rudder hinge), revealed the articulated remains of the tail of the ship, from the after end of the keelson to the sternpost. This portion of the lower hull was the narrowest part of the vessel, which ran aft below the waterline towards the rudder. A total of eleven 2 m2 excavation units were opened between August 1994 and June 1995 revealing articulated and disarticulated ship structure, rudder fittings, lead sheathing, and iron fastener concretions, as well as many other artifacts.
The stern architecture of the ship was exposed over a distance of 4.5 m, and included the after end of the keelson, eleven tail frames, lower hull planking, and the sternpost and stern knee. In addition, the rudder was encountered, along with its fittings. The surviving height of the stern structure is estimated to be 1.4 m, from the bottom of the keel to the eroded tops of the frames. The whole structure lists to port some 4 to 7 degrees, which corresponds to the port list measured amidships.
Keel
At the stern of the hull, the keel has a 20 cm sided thickness, which is 2 cm less than at midships. Heavy concentrations of corrosion products from the rudder gudgeon straps prevented measurements to determine the molded height of the keel, as well as the manner in which the sternpost was joined to the keel.
Sternpost
This straight timber (codaste) was the principal backbone of the stern of the ship, where the planking terminates, and on which the rudder was hung. Originally rounded at the after edge, the sternpost measures 35 cm in sided thickness and has a surviving molded height of 25 cm. Rabbets were cut 10 cm into the forward sided face, and 5 cm into the molded thickness, of the sternpost to let in hood‑ends of the planks and to provide a backing on which to fasten them with square-shanked iron spikes. The sternpost has an estimated rake (lançamiento) of 60 degrees of arc, measured upward from an imaginary horizontal extension of the keel (or, 30 degrees aft of vertical). San Diego, a Manila galleon lost off the Philippines in 1600, has the same sternpost rake (Carré et al. 1994: 148), while the more contemporary San Estéban, a Spanish nao wrecked in 1554 off Padre Island, Texas, had a slightly lesser rake of 65 degrees (Rosloff and Arnold 1984: 291).
Stern Knee
The stern knee served both as a brace between the sternpost and keel, and as a base for the after most frames. Fayed (fitted smoothly) to both the sternpost and keel, the stern knee is 21 cm in sided thickness and 20 cm in molded height at the forward end (lower limb), and 18 cm sided and 10 cm molded at the upper end (upper limb). The knee occupies a horizontal distance of 2.5 m and an estimated vertical distance of 65 cm. Two visible fasteners, an iron fastener 7 mm in diameter and a wooden treenail (cabilla de palo) 3.5 cm in diameter, fasten the stern knee to the keel. The iron fastener is located in a triangle-shaped recess at the forward and beveled end of the stern knee between Frames 7 and 8, and the treenail is situated between Frames 2 and 3. Fabricated from a naturally-curved timber, the stern knee has a thickened forward end which slopes downwards, forming a slight dip, before rising to meet the sternpost. A portion of the rising section, on the port side between Frames 1 and 2, has been beveled, possibly to remove an unwanted segment of spoiled wood. The vertical end is finished and smoothed.
Framing
Eleven frames were recorded in the tail section. The frames were given numbers from 1 to 11 for recording purposes. Frame 1 is located forward of the sternpost and upper limb of the stern knee, while Frame 11 is located at the aft end of the keelson. All the frames in this section are made of compass timbers (naturally curved pieces) to shape the concave after end of the ship. The first ten frames in this section of the hull were at one time Y‑shaped, while Frame 11 is V‑shaped in appearance. Only Frame 10 retained the original worked crook between the two frame arms. Environmental factors, i.e., natural decay and shipworm (Teredo navalis) activity, have degraded the crooks of the other frames and subsequently the rising line (gradual longitudinal rise in height of the frames to effect a narrow stern) from Frame 11 to Frame 1. On the after side of Frame 10 is a curious, but distinctive hole, 3 cm in diameter and 5 cm deep, the function of which is unclear.
Keelson
The after end of the keelson is located approximately 7.6 m from the cross gouged in the mainmast mortise. Notched over and let into Frame 11, the keelson measures 22.5 cm in sided thickness and 29 cm in molded height. On either side of the keelson parallel to the frame are two indentations. Perhaps these were deliberately scalloped from the keelson, or alternately, are the result of ballast rock abrasion across the timber’s surface.
Ceiling Planking
Only the tip of a common ceiling board was noted during excavation of the stern area. The board protruded from sediments adjacent to the keelson on the starboard side of the hull; its dimensions are 20 cm in width and 6 cm in thickness. The timber terminates in a roughly 45-degree angle.
Hull Planking
Both starboard and port sides of the ship’s tail section have four runs of surviving outer strakes. No stealers (short planks inserted between strakes) were observed. Plank dimensions are between 14 cm and 33 cm in width, and between 5 cm and 8 cm in thickness. At their hood-ends, the lower stern planks are 5 cm in thickness, equal to those of San Estéban (Rosloff and Arnold 1984: 293).
Curiously, no treenails have been encountered in the stern planking excavated thus far. These wooden dowels typically were used to fasten planks to frames below the waterline, since they were non-corrosive and swelled to make a tight fastening connection. Rather, iron fasteners were recorded in a pattern of two or three round-headed, square-shanked planking nails aligned vertically to fasten planks to frames. However, on the second plank below the eroded frame tops on the port side, an additional fastener was placed aft and between the aligned fasteners. Original fastener positions also are evident on some of the eroded frame tops, such as those on Frames 2 and 3, where planking nail grooves are still present. Corrosion products from iron fasteners between the frames and on the interiors of the planks, along with sediment buildup, have combined to mildly distort the hull’s original fair lines. Caulking samples from between hull planking were removed for analysis.
Fig. 19. Inboard profile of starboard hull planking showing the positions of frames and stern knee.
Rudder
By the 15th century, the axial, or stern, rudder had become a key component in the development of seagoing sailing ships. Made from dry beams of straight timber bolted together, the rudder (timón) hung from the sternpost on iron hinges and was operated by a long tiller (caña) that ran inboard to the main deck. To protect the rudder from accidentally becoming unshipped if the vessel ran aground, shipwrights sometimes fashioned the after most end of the keel into a skeg that sloped back to the forward edge of the rudder, which was curved accordingly. If the rudder did become unshipped due to unforeseen circumstances, it was saved from becoming lost by a rudder pendant (barón del timón) consisting of chains or ropes attached to the hull on each side of the rudder, or by a piece of rope that passed through a hole in the rudder and was made fast to the ship.
The ship’s rudder was found lying behind and to starboard of the sternpost. It appears to have fallen from the sternpost onto its port side sometime after the wrecking incident. Maximum surviving length of the rudder is 2.8 m. Maximum breadth of the rudder is 91 cm, slanting upwards from the leading edge to an eroded terminus. Three pintles, the pins that hung in gudgeons on the sternpost to form hinges, are still fastened to the rudder. A more detailed discussion of the rudder hardware and the information it contains about the shape of the stern is in the following chapter.
The rudder was constructed from two thick planks of wood, similar to the rudder of Mary Rose, flagship of Henry VIII that sank in 1545 (Rule 1982:71). Other rudders from the sixteenth-century such as the Villefranche wreck, an early 16th-century Genoese carrack sunk off the French Mediterranean, had at least four composite pieces (Guérout et al. 1989: 33-34). San Diego’s rudder was constructed from three timbers (Carré et al. 1994: 148), and San Juan’s was built from one timber (Grenier 1995 pers. comm.). Wood samples were taken from each plank and await analysis. Much effort and craftsmanship, from the carpenter to the blacksmith, went into constructing a ship’s rudder.
The two wooden pieces are edge-joined with at least three large (ca. 5 cm in diameter) wrought-iron drift pins, driven in from the aft edge of the after plank to join the forward plank. The forwardmost plank (called the main piece) represents the principal structure of the rudder, tapering in width from the lower forward edge which is 73 cm to the uppermost surviving portion. Overall length of this plank is 2.7 m. The forward edge of this plank has been beveled to a sharp point. At the location of each pintle, this edge has been hollowed out on the starboard side to form a recess 30 cm in length and between 8 cm to 10 cm in depth. In cross section the recess is L-shaped, with more of the port side half remaining, which partially encloses the gudgeon where its joins the pintle (see inset C, Fig. 20). A similar arrangement is also shared by San Diego’s rudder at its pintle positions (Carré et al. 1994:140), whereas San Juan’s rudder has less depth of wood removed along the pintle shaft, but is widened and deepened where the gudgeon supported the pintle (Parks Canada 1995, pers. comm.).
Fig. 20. The ship’s rudder was found lying on its side near the sternpost.
The after most plank (called the after piece) is much narrower than the main piece, averaging 18 cm in width, and surviving for a length of 2.68 m. Thickness of both rudder planks averages 5 cm at the eroded top of the rudder, to 18 cm at the leading edge, to 21 cm at the after edge of the rudder. At a distance of 2.45 m above its base, the aft end of the main piece is recessed 3.5 cm for a distance of 43 cm to let in the forward end of the after piece. Mary Rose’s rudder also was constructed in this fashion, although its main piece was let into the after piece (Friel 1994:90).
Remnants of surviving rudders from this period on the Mary Rose, San Diego, and San Juan, reveal that they were constructed of straight timbers, which, when joined together, assumed the rake of the sternpost. However, Emanuel Point Ship rudder’s main piece is not straight, sloping at a 5-degree angle from the forward and lowermost end towards the uppermost end. A preliminary reconstruction of the rudder’s juxtaposition with the sternpost suggests that, when the rudder was shipped (hung) to the 60-degree raked sternpost, it descended below the longitudinal axis of the keel. Although the forward edge of the rudder base has been diagonally sawn to fit on top of a skeg at the after end of the keel, the presence of a skeg was not verified during excavations, due to the large amount of corrosion products adhering to the lower portion of the sternpost and keel. In comparison, the rudder of San Juan is safely situated level with the keel and protected by its skeg (Grenier 1995, pers. comm.); however, the rudders of both San Diego and the Dramont “H” wreck, an 18th-century vessel located off France, descended below the plane of the keel and skeg (Carré et al. 1994: 141; Michel L’Hour 1995, pers. comm.). A possible explanation for the design of the low-slung rudder is that its drag through the water and vulnerability to unshipping were offset by the additional steering capabilities provided by an extra “bite” into water below the hull. Such a rudder is depicted on a contemporary drawing of a typical 16th-century Italian galley, in which quick and responsive maneuvering was necessary (Dotson 1994:160).