Figure 74 – uploaded by Taras Pevny

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Fig. 78. Close-up of the chop marks in the stern deck planks. (Photo T. Pevny) — Figure 78 Close-up of the chop marks in the stern deck planks. (Photo T. Pevny)

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Fig. 1. Model of the Philadelphia. (From Sands 1988: 154) Fig. 2 & 3. Peter Fix working on the stern deck of the Philadelphia. Note the bench/locker on either side of the vessel. Taras Pevny looking for marks under the starboard bench. (Photos by T. Pevny & P. Fix)

II. Meeting a Need: The Historical Role of Bateaux Gondolas are double-ended boats with flat bottoms. A double-ended hull comes to a point at both ends, thus the complexity of building the stern structure associated with square transoms is avoided (Fig. 5c). The wide flat bottoms result in a large amount of volume within a short height of hull (depth of hull) (Fig. 5a). As a consequence, due to the laws of buoyancy and displacement, these types of hulls can carry a large amount of cargo, men and artillery in the case of the Philadelphia, without floating very deep in the water (shallow draft). In inland and coastal waterways this limited draft allows for traversing over shallow waters or underwater hazards. It also allows the smaller and/or lighter versions of these vessels to be beached — for the night, to make repairs and/or long- term storage — or portaged from one waterway to another (Figs. 6 & 7). vy. , 44%. a. 1.7... 1 ...%4. 1 ££... gh. .*°.. iG Ft lg gl ld 4G lg ge

were often built in remote regions, for specific short-term purposes, by individuals with limited finances, tools, shipbuilding skills and time — in _ short these vessels were appropriate for their building environment. Fig. Sa-c. Overall views of the Philadelphia. Plans by H. Hoffman for the Smithsonian Institution. (After Bratten 1997: 162 &167.

Fig. 6. Flatbottom Mackinaw boat pulled up on a riverbank. (From American Heritage 1961: 108)

Fig. 7. Vessels being portaged between waterways. (From American Heritage 1961: 72)

Fig. 8. A Flatboat being steered downriver. Flatboats, essentially square barges, could not be taken upriver. (From American Heritage 1962: 26)

Fig. 9. A keelboat crew fending off an attack. Keelboats could be poled, rowed or sailed upriver. (From American Heritage 1961: 82)

Fig. 10. Replica of the Lake George bateau. (From Crisman 1988: 131) Our recent discovery of carpenter marks on the Philadelphia opens up a great opportunity to stimulate such research and publication (see Section VI). Additionally exciting is an ongoing effort to study and possibly raise Philadelphia’s sister ship — another gondola that sank along with the Philadelphia during the battle of Valcour Island in October of 1776.'4

Fig. 12. Replica of the gondola Philadelphia. (From Bratten 2002: 153)

Fig. 11. Replica of the James River bateau. (From Crisman 1988: 131)

Fig. 13. Howard Chapelle’s reconstruction drawings of the Philadelphia based on an examination of the remains. (Chanelle 1949: 109) The remains of the Philadelphia were first described in print by Lorenzo F. Hagglund, who discovered and recovered the vessel in 1935 and was its caretaker till 1961, when it was transferred to the Smithsonian Institution.45 On the basis of this discovery Howard I. Chapelle generated reconstructed plans of the vessel that were published in 1949 in his book The History of the American Sailing Navy (Fig. 13).!© Subsequently, the overall shape and construction of the hull remains were extensively documented, reconstructed, described and illustrated by Howard P. Hoffman in a set of annotated architectural drawings, as well an article in the early 1980’s (Figs. 5, 18, 23, 34, 62, 75).!7 The construction of the Philadelphia and that of the Lake Champlain gondolas was also researched in the 1980’s by graduate student William A. Bayreuther.'® The discovery and preservation of the Philadelphia, and the historical events associated with it, inspired the construction of a replica by the Lake Champlain Maritime Museum from 1989 to 1991 (Fig. 12).!9 The building of the replica provided an opportunity to once again evaluate the boat’s construction and its performance under sail and oar. The work of Chapelle, Hoffman and Bayreuther, as well as the lessons from building and operating the replica, were incorporated into a dissertation in 1997 and subsequently into a book in 2002 by John R. Bratten, who presented the archaeological remains of this vessel and the associated artifacts in their immediate historical context.?°

Fig. 14. A straight plank’s normal or natural run along the bilge of a hull. (After Greenhill 1988: 137) iene: Sitar” ji ——— ee a ee ae The underlying concept was a desire to quantify the normal or natural run o a plank or ribband (a small temporary plank used during construction, also referred to as a batten) along the length of the hull. A “normal” run is the way a plank, specifically a straight plank, bends along the curvature of a hull without any edge-set — forced bending in an edgewise direction (Fig. 14). Currently, the best archaeological example of the culmination of this design concept is the hull of La Belle, a late 17" -century French vessel, whose design I had the privilege to study.2! La Belle has design marks carved into its timbers along two longitudinal bilge curves (Fig. 15). Its design represents the beginning of the final stage in the development of geometric/arithmetic methods of quantifying hull curvature before the introduction of modern orthographic hull design in the form of the lines drawino or lofted halfemodel cectione

Fig. 15. Isometric drawing of La Belle’s hull remains with every third “marked” frame set depicted. The red lines depict the diagonal design curves indicated by the shipwright’s marks. (Drawing by T. Pevny)

Fig. 16. A French drawing from 1683 depicting the “diagonals” method of design. Note in the profile view the diagonals are depicted as actual ribbands. (Afer Boudriot 1998: 54-55)

Fig. 17. Basic beginning steps of a flat bottom dory's construction. The chine/bilge curve has been highlighted in red. (Afer Gardner 1987: 58)

Fig. 18. Profile and plan views of the bottom planks and framing of the Philadelphia. The centerline is highlighted in red and the plank seams are highlighted in blue. Adapted from H. Hoffman’s plan for the Smithsonian Institution. (After Bratten 1997: 153) 1.1) The Philadelphia is a double-ended flat bottomed vessel. Its bottom 1 composed of planks laid lengthwise edge-to-edge. The keel less bottom is completely fla with no lengthwise curvature (rocker) or lateral rise (deadrise). In this simple form o construction, the shape of the bottom defines the main shape of the vessel. Because th bottom planks lie in a single flat plane, drawing the shape of the curved edges of the hul is comparable to drawing such a shape on a flat sheet of paper (Fig. 17).

€ Fig. 19. Upside down dory construction. (From Gardner 1987: 71)

Fig. 20. The construction of a replica of the Bevaix boat based on the remains of this Gallo-Roman boat. (From Hocker 2004: 69) Fig. 21. A turf boat under construction in Britain in 1970. Note the bottom is a single slab of timber. (Fro Greenhill 1995: 29)

Fig. 22a-b. “V” scribe mark pointing to the centerline location under the keelson. The mark is highlighted in 22b. (Photo by T. Pevny) Although the Philadelphia’s bottom planking is not laid out symmetrically relative to t he centerline the actual chine curves are mirror images of each other. A chine is an angled bilge instead of a round or curved bilge. To lay out these curves symmetrica centerline. have not id ly on either side of the bottom the shipwrights needed to establish a Presumably a string was stretched between the two end points. Thus far we entified a longitudinal centerline scribed into the wood. Unfortunately, the inboard face of the bottom planking can only to be examined in one location along the centerline. However, in this location we did find a scribed-in “V” mark pointing to the centerline (Figs. 22a-b & 23). There is a good chance that this mark is not unique; only future investigation will tell.

Fig. 23. Plan view of the Philadelphia showing the location of the centerline “V”. In this small area the bottom planks are visible from above. This was probably left open to allow water to be bailed out — a bailing well. Adapted from H. Hoffman’s plan for the Smithsonian Institution. (After Bratten 1997: 157)

Fig. 24. Plan view of the bottom planks and framing showing the main proportions and the positioning of the maximum breadth. Adapted from H. Hoffman’s plan for the Smithsonian Institution. (After Bratten 1997: 153) The intentional proportioning of the bottom’s main dimensions is an indication of the execution of a predetermined design. What evidence supports the use of these basic mathematical relationships, and how can we hypothesize that these were intentionally established by the shipwrights and are not the product of archaeological wishful thinking?

Factoring in the badly eroded state of the timber surfaces, enough floor-scribe marks were identified to strongly support the preliminary conclusion that the floor locations were marked along the entire length of the hull. Traces of such marks were identified at floor divisions #5, #6, #11, #12, #13, #33, #36 & #38. Most importantly, these lateral scribe lines were found in the extreme stern where there are no floor timbers. Fig. 25a-b. Floor scribe line at floor division #38. Frame #38 is labeled in green. Note in this location there is no actua floor, just a marking for its location (i.e. floor division #38). (Photo by T. Pevny)

Fig. 26a-b. Floor scribe line at floor division #36 (Floor #34). Frame #36 is labeled in green. (Photo by T. Pevny)

Fig. 27a-b. Floor scribe line at floor division #33 (Floor #31). Frame #33 is labeled in green. (Photo by T. Pevny)

Fig. 28. View of the lower port stern of the Philadelphia. The floor scribe mark from Fig. 25 is highlighted. Note the missing chine plank. (Photo by T. Pevny)

Fig. 29. Plan view of the bottom planks and framing. Floors are numbered in red. Floor divisions are highlighted and numbered in blue. Frames are numbered in green. Adapted from H. Hoffman’s plan for the Smithsonian Institution. (After Bratten 1997: 153) The Philadelphia has 34 floor timbers spaced at 15 inches from the corresponding edge of one timber to another (room and space) (Fig. 27). Beyond the forward most and aftermost of these floor timbers there is room for two more floor timbers respectively. Given the discovery of lateral scribe lines in the extreme stern where there are no floor timbers (Figs. 25, 28, 29), it seems the shipwrights subdivided the bottom into 39 divisions of 15 inches in length thus giving a theoretical length of 48 feet 9 inches (Fig. 29) versus the documented length of 48 feet 10% inches.?® Bratten notes Hoffman’s suggestion that “the position of posts, floor timbers, and frames could have been marked”.?? Our discovery shows that at least in the case of the floor timbers the positions not only could have been marked — they were marked.

Fig. 30. Cant frames reduce the amount of beveling necessary to fit the outboard curvature of the hull. (After Greenhill 1988: 116)

Fig. 31a-b. Floor scribe line and “V”at floor division #38. Frame #38 is labeled in green. (Photo by T. Pevny

Fig. 32a-b. Floor scribe line and “V”at floor division #36 (Floor #34). Frame #36 is labeled in green. (Photo by T. Pevny)

Fig. 33a-b. Floor scribe line and “V”at floor division #33 (Floor #31). Frame #33 is labeled in green. (Photo by T. Pevny)

Fig. 34. Profile view from the lines drawing combined with the plan view of the bottom planking and framing. The lines drawing cross-section lines are highlighted in red. Adapted from H. Hoffman’s plans for the Smithsonian Institution. (After Bratten 1997: 153, 159)

Fig. 35. Reconstructed building sequence of the 14" -century AD Bremen Cog discovered in Germany. (After Greenhill1988: 54, 56

Fig. 37. 17" -century French method of frame-first construction. Note the bilge ribband set up early in the early stages of construction. From the Album de Colbert, 1670. (After Rieth 1996: 46) Fig. 36. Two stages in the construction of a 17" -century Dutch fluit. In this building tradition the bottom was built plank-first using temporary cleats to hold the planks together until they were secured with frames. The upper hull was built frame-first. Model by Albert Hoving. (After Hoving 1997: 30-31)

Fig. 40. Reconstruction of the 2 -century AD Blackfriars ship discovered in London. Its construction sequence is very similar to that of the Philadelphia. (After Greenhill 1988: 41)

Fig. 39. Boat under construction in Turkey in 1995 using the ribband method of design. The shape of the vessel was defined using ribbands on one side of the vessel and complete frames were cut to fit. (Photo by T. Pevny) Fig. 38. 18" -century French method of frame-first construction. Note the bilge ribband set up in the early stages of construction. (After Rieth 1996: 49)

Fig. 41. Plans and photograph of the 1* -century BC Commachio wreck discovered in Italy. The seams of the hul planks are sewn together. (After Berti 1990: 36 & 41)

Fig. 43. Process of building a skiff by first bending the side planks. (After Chapelle 1941: 217) Fig. 44. Cross-planked bottom on a small boat. (From Gardner 1987: 5)

Fig. 42. End view of the planking runs of one of the 2™ -century A.D Nemi barges. The seams of the hull planks are joined with mortise-and-tenon joints. (After Ucelli 1950: Plate VIII)

Fig. 46. Radii used to lay out the Philadelphia’s frames as determined by H. Hoffman. Note that frames 13-30 were determined to have the same radius of 7 feet 5 4 inches. (After Hoffman 1982: Sheet 3) Studying the shape of the standing knees, Smithsonian researcher H. Hoffman came to the conclusion that in the central section of the vessel the knees were all cut to the same radial curve of 7 feet 5% inches (Fig. 46).! This allowed many such knees to be mass produced for all the gondolas under construction, thus significantly simplifying their production.*? Towards the ends of the vessel the curves of the knees were flattened by increasing their radii. This melded the curvature of the sides smoothly into the end posts of the vessel (Fig. 47).

Fig. 45. A plank being bent onto the raised frames on the replica of the Philadelphia. Note the wales were attached first. (After Bratten 2002: 150)

Fig. 47. Diagram showing the proposed method of designing the midship shape. The design lines are superimposed over H. Hoffman’s cross-sectional drawing of the Philadelphia’s hull shape. (After Hoffmar As was already discussed, the knees were canted and there was only a minimal need to trim their outer faces to fit the curvature of the sides, known as dubbing if an adze was used. Once the correct curvature for each of the knees was determined by the shipwrights, the work of cutting and positioning these knees was relatively simple and easy.

Fig. 49. Illustration showing how increasing flare results in greater rise. (After Gardner 1987: 85) Fig. 48. Illustration showing how flare of the sides of a vessel results in the rise at the ends of planks. (After Landstrom 1970: 20)

The shapes of a dory’s planks are a good illustration of the end result of spiling (Figs.51-52). A dory’s hull shape is a smaller version of that of the Philadelphia with more exaggerated curvature. As in a dory, the lower plank(s) of the Philadelphia had to have been spiled (Fig. 53). In the case of the Philadelphia this was done within the span of the lower two planks. Fig. 50. Illustration of the characteristics of the lower plank run of a dory. The differential gap between a parallel- sided plank bent along the hull and the flat bottom is highlighted in red. (After Gardner 1987: 91)

Fig. 52. A partially assembled dory illustrating how properly shaped planks enclose the hull. (After Greenhill 1995: 188) Fig. 51 Photograph of the flattened planks that compose a dory. Note the shape of the lowest side planks. (After Greenhill 1995: 66)

Fig. 53. A view of the starboard stern of the Philadelphia. The lower strakes are highlighted in red. The unfairness in the run of the wale is indicated by the red arrows. (Photo by T. Pevny)

Fig. 54. Using a batten to line-off the seams on a more amnlaw hall (A ftar Ceannh:l] 1022: 120)

Fig. 56. Knuckled frames of a Swampscott dory. (After Gardner 1987: 76) Fig. 55. A view of one of Philadelphia’s frames between the inner and outer planking. Note the flats between the seams. (Photo by P. Fix) 49) ine outer surface ofr the hull planks is highly degraded, and, thus far, we have not found any spiling marks. Fortunately, such marks were found elsewhere on the hull (see Section V-3.1). Nonetheless, the marks across the edges of the hull planks at the frame locations seem to directly relate to the process of cutting out and/or shaping the laid-out plank shapes (Fig. 58a-b). A cursory examination of just two seams in the starboard stern revealed 26 such marks at consecutive frame locations. Several possibilities exist as to what construction procedure resulted in these marks.

Fig. 57. Crowning and hollowing of planks to fit the curved surface of a frame. (After Greenhill 1988: 141)

EVEN RN ER IRE CEE WN UR RRR MCR COLE, BE) ABO, OL VED Whe Remains of evident relieving cuts are preserved on the forward face of the Philadelphia’s stem (the centerline timber in the bow) (Fig. 60). At first glance these marks seem to be scribed in draft marks — marks used to indicate how deep the vessel is sitting in the water. However, they are not set at increments in feet nor are they regularly spaced (Fig. 61a-b). These marks are simply cuts made to ease the shaping of the curve of the stem timber. The stem rabbet, like the midship frames, is cut to a 7/4 foot radius curve. The rabbet is the notch into which the ends of the hull planks are fitted. The outer edge of the stem is an 8% foot radius curve.?” Fig. 58a-b. Edge mark across the edge of a hull plank at a frame location. (Photo by T. Pevny)

Fig. 60. Closeup of relieving cut marks on the stem of the Philadelphia. (Photo by T. Pevny) Fig. 59. The use of relieving cuts when cutting a curved timber (From Greenhill 1988: 108) The plank edges were angled or beveled to form a wedge-shaped seam for caulking. Caulking is usually some form of fiber, coconut fiber in the Philadelphia’s case, which is driven into the seams with caulking irons to make them watertight.*® Shipwrights usually measure the bevel angles at the frame locations and then cut notches at those angles at corresponding positions along the plank edge. These cuts guide the beveling of the entire edge of the plank. It is possible that the preserved edge marks are the remains of such beveling notches.

Fig. 6la-b. Relieving marks on the stem of the Philadelphia. (Photo T. Pevny)

Fig. 62. Profile and plan views of the deck structures of the Philadelphia. The red arrows point to the benches/lockers. In the profile view the port spiling marks are drawn in red at their approximate locations. In this view the side of the locker is not shown for the marks to be visible. Adapted from H. Hoffman’s plan for the Smithsonian Institution. (After Bratten 1997: 162) 3.1) Fortunately, and quite unexpectedly, we did find probable spiling marks preserved on some of the Philadelphia’s internal planks (ceiling planks). In the stern of he vessel there are two benches/lockers along either side of the hull (see Figs. 2, 62). When we lifted the seat on the port side, we noticed that the plank surface was better preserved than in other places on the hull. Brushing off the accumulated dust and shining a raking light over the inboard surface of the ceiling plank (Fig. 3) revealed five fairly well-preserved “V” scribe marks pointing to the upper edge of the ceiling plank (Figs. 62-69). One of the “V’s” also had traces of a centerline (Fig. 69). We are unaware of any other marks such as these having been archaeologically identified on American shipwreck remains.

Fig. 64. The port spiling marks highlighted in red. Note the curvature of the upper edge of the plank. (Photo by T. Pevny) Fig. 63. The port spiling marks highlighted in red. (Photo by T. Pevny)

Fig. 65a-b. Port spiling mark #1 from the stern. Note that the mark is preserved in the very fragile and fragmented outer surface of the plank. (Photo by T. Pevny)

Fig. 66a-b. Port spiling mark #2 from the stern. (Photo by T. Pevny)

Fig. 67a-b. Port spiling mark #3 from the stern. (Photo by T. Pevny)

Fig. 68a-b. Port spiling mark #4 from the stern. (Photo by T. Pevny)

Fig. 69a-b. Port spiling mark #5 from the stern. (Photo by T. Pevny)

Fig. 70. Compass method of spiling the chine plank on a dory. (After Gardner 1987: 89, 92)

Fig. 71. The starboard spiling marks highlighted in red. (Photo by T. Pevny)

Fig. 73. Starboard spiling mark #2 from the stern. (Photo by T. Pevny) Fig. 72. Starboard spiling mark #1 from the stern. (Photo by T. Pevny)

Fig. 74. One of the carpenter marks uncovered during the renovation of a 1940’s bathroom. (Photo by T. Pevny)

Fig. 75.Profile view of the supporting deck structures of the Philadelphia. The red arrows point to the locations of the beam notches that supported the mortar platform. Adapted from H. Hoffman’s plan for the Smithsonian Institution. (After Bratten 1997: 157) 4.1) The spiling marks were not the only marks preserved on these ceiling planks. Originally the Philadelphia had a higher deck in the stern that supported a mortar cannon.*! Notches were cut in the ceiling planks to fit the beams supporting this deck. After an accident in which the mortar exploded, the gun and the deck structure were removed. However, the notches in the ceiling planks remained (Fig. 75). Originally the shipwrights marked the locations for these notches with scribe marks. Such marks are clearly visible on the same plank surface as the ceiling plank spiling marks (Fig. 76).

Figure 74 – uploaded by Taras Pevny

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