We would like to express our gratitude to the Croatian Ministry of Culture, Municipality of Pašman, and the Association for the Promotion of Underwater Archaeology (FUWA, Koblenz, Germany) for supporting the underwater excavations; Charles Bendig, David Ruff and Christopher Dostal for English editing and providing valuable suggestions and corrections.
1The lowly ship’s pump can play a significant role in saving a vessel during calamities. When parts of the ship crucial for propulsion and manoeuvring do not work and water is leaking through the seams filling the hold, it is still possible to save everyone onboard by pumping the water out. Except for Thomas Oertling’s publication, Ships’ Bilge Pumps (1996), which discusses this crucial ship component from the 16th to 19th centuries, there is a lack of additional archaeological evidence for ships’ pumps on other 16th-century vessels (Waddell 1985; Loewen 2007; McElvogue 2007; Guérout 2017). In a recently published article, Charles Bendig (2020) discusses pump technological developments based on archaeological evidence from 300 BC to 1600 AD, considering the position of the ship’s pump within the hull.
2Although a fair number of chain and force pumps were attested on ships from antiquity (Stein 2007; Carre 2007), it is unknown exactly when common and burr pumps were first invented. Drawings from historical sources suggest they came into use by the middle of the 15th century. Subsequent drawings of similar pumps used for mining in Germany are described by Gregorius Agricola in his treatise De Re Metallica (1556). Pumps of similar designs were also used on ships from the same period. In fact, circular lead discs recovered from the 16th-century Molasses Reef shipwreck were identified as the valves of a common pump based on Agricola’s drawings (Oertling 1989, p. 586 and 587, 1996, p. 22-23 and 34-35).
3Contrary to the force pump’s reliance on two solid pistons working in tandem, burr and common pumps utilise two permeable valves to lift water through a single tube. Ancient chain pumps are predominantly mechanical and lift water using a series of discs strung on a rope (Stein 2007; Carre 2007).
4Burr and common pumps co-existed in the 16th century, while in the 17th century the burr pump fell out of use. Both types of pump had a stationary lower valve, installed either just below the pump tube as part of a separate wooden foot or inside the tube itself (Waddell 1985; Loewen 2007). The only definitive way to distinguish between these two pump types is based on the type of upper valve used (Oertling 1996, p. 21 and 24).
5Excavations of the Gagliana Grossa, which sank in 1583 near the Gnalić islet off the coast of Croatia, yielded an interesting find in 2016. After removing a layer of ballast stones, archaeologists discovered a vertical rectangular timber with smooth sides. Upon further examination, the timber had a central vertically drilled hole, and the lower end was stepped to fit between floor timbers. Based on its position in the middle of the ship and analogies with published archaeological data, the object was identified as the lower part of the pump tube for a ship’s pump. It was surrounded by upright positioned planks forming a structure interpreted as the pump well.
6During the 2017 and 2018 field seasons, it was decided to remove parts of the structure to conduct recording in the laboratory. Observations, sketches, and photos were made, as well as a photogrammetry model. After recording, the removed components were wrapped in geotextile and stored safely back on the site.
7Although the lower tube and the pump well assembly were well preserved, the remainder of the pump equipment, such as the valves, rod, breaks, or an associated dale, did not survive.
8The pump complex was composed of two elements.
9Measurements: bottom, 23 × 28 cm; middle, 30 × 28 cm; diameter of the hole, 11 cm (upper), 9 cm (lower); preserved height, 30 cm (fig. 1).
Fig. 1: Lower part of the pump tube
(drawing: K. Yamafune, K. Batur)
10The surviving element of the pump tube is made from a single timber originally found standing in an upright position amidships. Each vertical edge of the tube is chamfered, with a circular hole drilled vertically through the centre. Two sides of the rectangular base are rebated to allow the tube to fit between adjacent floor timbers. The tube was installed between the fourth and fifth aft floor timbers to reach as deeply as possible into the central bilge.
11Water that accumulated in the lowest part of the ship was pumped out through the central bore. No material evidence was found on site for the lower and upper valves. As there was no foot below the pump tube, the lower valve was probably made of leather and/or metal installed in the missing part of the pump tube. Survival of the upper valve attached to the movable rod would allow us to distinguish whether this pump was a burr or common type.
12Measurements: overall dimensions, 163 × 97 cm; height, 87 cm (fig. 2).
13The pump well is an enclosed structure formed to protect the pump components from ballast stones, other cargo, or debris present in the hold of the ship (Waddell 1985, p. 251). In the Gnalić shipwreck, the pump well was built on the starboard side, formed by walls made of upright positioned planking, stanchions, and a buttress. On the southern side, the structure was defined by two internal stanchions, which were fixed in place between two stringers. The western wall has a foundation on the first, western buttress. Pump well height was achieved by installing the pump well planks vertically.
Fig. 2: View of the middle ship area, focusing on the ship’s pump and mast step
(orthophoto: K. Yamafune)
14Similar systems of drainage have been found on other 16th-century ship excavations, including the Basque whaler San Juan, lost in 1565 in Red Bay, Canada, and the Lomellina, lost in 1516 at Villefranche-sur-Mer, France. San Juan carried a burr pump, based on the upper valve formed as a leather cone attached to the end of the rod (Loewen 2007, p. 164-167). Conversely, it is not possible to define the type of pump on Lomellina, as only the lower foot valves were preserved (Guérout 2017, p. 5-8). In contrast, the ship’s pump excavated on the Gagliana Grossa appears to have just one long tube without a lower foot valve to act as a base. The find from Gagliana Grossa is especially important, as it is possibly the earliest archaeological evidence of a pump tube without the use of a foot on a ship intended for Mediterranean sailing (table 1).
Table 1: 16th-century archaeological evidence of ships’ pumps
Site |
Date |
Pump position and type |
Tube parts |
Operational location |
Reference |
Lomellina (Villefranche-sur-Mer, France) |
1516 |
Main pump; unknown |
Lower foot, tube |
Mediterranean |
Guérout 2014, p. 4-7. |
Molasses Reef (Turks and Caicos Islands, UK) |
1520s-1530s |
Unknown; common |
none |
Transatlantic |
Oertling 1989. |
Mary Rose (Solent, UK) |
1545 |
Spare pump; unknown |
tube, internal lower valve |
Northwestern Europe |
McElvogue 2007, p. 289-292. |
San Juan (Red Bay, Canada) |
1565 |
Main pump; burr |
Lower foot, tube |
Transatlantic |
Waddell 1985; Loewen 2007, p. 164-167. |
Gagliana grossa (Gnalić islet, Croatia) |
1583 |
Main pump; unknown |
Tube |
Mediterranean |
Radić Rossi, Nicolardi 2019, p. 75. |
15The Gnalić shipwreck contains a ship’s pump structure preserved at midship on the starboard side. Construction of the pump well is closely related to the mast step assembly. In this case, the western wall of the pump well was installed over the mast step’s first buttress. The overall area surrounded by the other three preserved walls of the pump well encompasses one third of the mast step area.
16The only part of the ship’s pump recovered was the tube. The original height of the tube is unknown, as the surviving upper portion is quite damaged by shipworms and there is still not enough data to assume the overall height of the hold. Absence of any evidence for the lower valve possibly demonstrates that Gagliana Grossa went through another phase of ship pump development. The foot base probably disappeared from use because it made the pump tube difficult to clean and maintain during a voyage (Oertling 1996, p. 21). A future site discovery of the pump rod would permit full analysis of the type of ship pump installed on Gagliana Grossa based on the appearance of upper valve attached to the rod.
17Although studies of the ship pump from the Gnalić shipwreck are still in progress, the current results have significantly contributed to understanding the overall evolution of the ship pump.