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5. Construction and Engineering
- University Press of Florida
- Chapter
- Additional Information
5. Construction and Engineering •• In describing ships and nautical engineering, the concept of scale is a difficult one with which to grapple. The size of ships and marine structures is often illusory, seemingly more dependent on individuals’ internal perception and experience than on actual solid measurements.Most scholars would agree, however, that no matter whether we are talking about size or scale, it is difficult to describe in any meaningful or true-to-life fashion just how large ships and their associated machinery are unless the listener or reader has experienced a ship firsthand. Only the familiarity of standing on or next to one of these mobile edifices imparts the necessary sense of proportion needed to understand scale.Good maritime museums capitalize on the concept of scale in exhibit design,using real machinery and ships to convey their gigantic size to visitors firsthand. The problems involved in describing scale pale in comparison to accurately interpreting a structure’s engineering performance. Engineering performance is complex and invariably combines scale, movement, stress, and material properties with external forces such as gravity or buoyancy. Some of these variables—how a building sways in the wind or how a ship’s hull works and twists in heavy seas, for example—cannot always be perceived by our senses. The structure’s movement might be too minute to see or impossible to perceive from our particular vantage point. To make matters worse, engineering description is confined by necessity, particularly in book and journal form, to measurement, mechanical drawing, and photographs bound together with explanatory language.These are clumsy tools for depicting and conveying the motion of a complex, three-dimensional object as it moves, 86 strains, flexes, or vibrates. Perhaps a better or more accurate tool for describing engineering is a scale model. Small-scale models give an object of study three dimensions and visually represent a ship very accurately, often allowing for the best combination of description with illustration. For this reason, many nautical archaeology projects now include the construction of three-dimensional representations of an entire shipwreck or of its sections. In addition,the model-building process itself can provide insight into otherwise imperceptible problems and the engineering solutions put foreword by shipbuilders. In this way, model building becomes applied archaeology, a way to perceive shipbuilding without benefit of historical or archaeological records. Model building also gives us essential hints into a structure’s inherent engineering strengths and weaknesses.Though small-scale models rarely exhibit the exact physical attributes of a ship in its marine environment, they are invaluable in demonstrating how a complex structure works under stress in three dimensions.170 For these reasons a scale model of the stern section of Montana, based on measurements,drawings,and photographs compiled during the archaeological project, was developed specifically to answer questions concerning the engineering of the vessel (see figures 36 and 41). As an added bonus, the activity of model construction gave us much-needed insight into how the Montana was constructed. A model was essential in the Montana’s case, as the hull and service environment were so unlike anything the archaeologists had previously studied. The model became a sort of crib note to understanding the effects of engineering and nature on the ship, an effort to “reverse engineer” the vessel.171 Such an undertaking isn’t always easy; it requires a great set of archaeological field notes and an engineering sense of material properties and scale, all blended with a healthy dose of practical experience in ship construction, ship operation, or both. Not surprisingly, historical sources are invaluable to any archaeologist attempting to recreate the qualities of a ship, particularly accounts that describe steaming or sailing attributes that verify archaeological observations. The wooden model, first visited in the illustrations for chapter 4, proved useful in three major ways: it demonstrated a likely method of construction for Montana; it verified Montana’s hull flexibility; and it confirmed how Construction and Engineering · 87 [44.220.43.170] Project MUSE (2024-03-29 12:07 GMT) Montana’s engineering was integrated into the hull, a process which will be described in the course of this chapter. Construction It seems likely from the model construction that Montana was built in simple prefabricated pieces and assembled on the ways. This method would have been cost effective and efficient given the ship’s abnormally large size and the constraints imposed by it. The slipway must have consisted of an elevated, flat construction bed on which a keel plank...