Aft Cargo Hold
The deck and deck beams covering the aft cargo hold are intact but have suffered severe damage. All deck beams observed in the confined space are broken approximately 3 feet from the port side causing the central portion of the deck to sag along the break. Using the known depth of hold as a reference, the sag is approximately 1.1 feet along the centerline and increases to 2.5 feet at the break. The sag is clearly illustrated in the cargo hold wall profile of Figure 29. The cause of the break is unknown although it does not seem to be from age induced deterioration. A segment of a deck beam examined on the surface was physically sound and very buoyant. The broken outboard end is badly splintered suggesting a violent blow or explosion as the cause. This damage may be the result of Ross's demolition work.
The deck beams extend from the hull to support the port paddle guard in the same fashion found on the starboard side. The beams are broken in the same way as those on the starboard guard allowing the guard to sag. Examination did not extend far beyond the hull and no details on the guard were gathered. There are two possible explanations for the identical damage on the port and starboard sides. First, Roderick Ross may have deliberately caused the damage while clearing the site in the 1880's. Second, the heavy guards on side wheel steamers suffered from transverse hogging forces that caused them to sag. To combat the problem, builders used a system of sampson posts placed along the keelson with hogging chains attached to the guards to provide support (Bates 1968:28-29). If the system broke down after the vessel sank due to natural or manmade wrecking processes, the guard would eventually sag and break off the ship. Presently, however, there is no evidence to indicate the Maple Leaf had this type of hogging system.
Construction details noted in the forward area continue in the aft cargo hold. Deck beams are spaced on 24 inch centers, sided 5 1/2 inches and molded 7 inches. Although cargo hindered a close examination, a deck clamp did support the beams at the side of the hull. A dagger knee provided additional support. The top of the knee angles aft, away from the machinery spaces amidships. This is the opposite direction of the diagonal knees found on the forward starboard side. It is further evidence of an internal longitudinal support system.
Deck stanchions along the keelson provided the deck with additional support. One stanchion, removed for examination, was located at 137.5 feet on the baseline. The top originally fit into a rectangular mortise on the underside of a deck beam but came loose when the deck collapsed. It measures 9 feet 2 1/2 inches long with a 5 inch square base. The upper half, measuring 4 feet 11 inches long, is machine turned and has rope wear marks.
The internal architecture of the hold appears undamaged and the material packed inside certainly reflects information on stevedoring practices of the period. The small area open for examination, however, allows only tentative description of the interior construction. The main feature appears to be an internal, or lower deck, approximately 3 feet above the bilge ceiling. The cargo inside the hold is packed on this lower deck.
This internal deck is planked with tongue and groove boards 4 1/4 inches wide and 7/8 inch thick laid longitudinally. The deck stanchion passed through the lower deck and the planks were fitted around it and not attached. Removing the stanchion provided a 5 inch square opening to examine the underside of the deck. All measurements taken through the hole are approximate. The planking is fastened to 2 by 4 inch transverse beams spaced on 18 inch centers. A large timber, tentatively identified as part of the keelson, rests 24 inches below the top of the deck. It is 6 inches wide on top and 12 inches deep. Wear marks on the stanchion, 24 inches above the base, were caused by the deck planking and confirm the height of the deck above the keelson.
The Maple Leaf's depth of hold is 10.6 feet (10 feet 7 1/4 inches) amidships (Certificate of Ownership 1851). Reconstructing the stanchion/deck beam arrangement approximates this measurement. It also places the lower deck roughly 7 feet 7 inches below the underside of the main deck. This deck is lightly built considering the timbers used in construction and may represent a temporary structure. A final interpretation will have to await future work to expose more of the structure. Further historical research may also shed more light. An illustration (Figure 11) of the 1855 steamboat Commonwealth in John S. Russell's Naval Architecture presents a similar arrangement with deck stanchions passing through the lower deck (Russell in Hilton 1968:endpapers).