CARLETON ISLAND UNDERWATER ARCHAEOLOGY PROJECT SUGGESTED APPROACH

Transcription

1 CARLETON ISLAND UNDERWATER ARCHAEOLOGY PROJECT SUGGESTED APPROACH

2 - 1 - CARLETON ISLAND UNDERWATER ARCHAEOLOGY PROJECT SUGGESTED APPROACH SITE: Sunken remains of a wooden sailing vessel, probably late 19th century in North Bay, Carleton Island, St. Lawrence River, Jefferson County, New York. During 1775 the British government located supply stores on the island to which supplies from Montreal and Quebec could be dispersed to the lakes areas. On August 12, 1778, Lieutenant John Schank, of the Royal Navy, arrived at Carleton Island. He had been dispatched to this area by General Frederick Haldimand to choose the most advantageous site at the head of the river to construct a fortified base to act as a transshipment point for military and navel supplies. After inspecting and rejecting Cataraqui, (Kingston), Lieut. Schank chose Buck's Island (as it was then called, although the French had earlier named it Isle aux Chevreuils). In a letter to General Haldimand on August 17, l778, Lieut. Schank reported that he had selected this place because of its high ground commanding a full view of the entrance from the lake and its harbor "where I found three fathoms of water. It will excellently accommodate loaded vessels of any burthen whatever. The island was renamed in honor of Governor Sir Guy Carleton (Lord Dorchester) and construction of fortifications and harbor facilities was started at once. The fort was named Fort Haldimand in honor of General Sir Frederick Haldimand who succeeded Carleton as Governor of Canada at about this time. A pier about 110 feet long and a shipyard was constructed on the shore of the island. During the remainder of the revolution, this base served as one of the major staging areas for military actions against the Patriots, and it was also a rallying and camping spot for Indian allies of the British. It was from Carleton Island that the bloody raids of Butler's Rangers and the Iroquois war parties were launched against the Mohawk Valley. Joseph Brant visited here, and the British built a house here for his half sister Molly, where she lived for the duration of the war. As many as 800 troops were garrisoned at Fort Haldimand, and the ships of the Provincial Marine on Lake Ontario wintered at Carleton Island. Several of the larger naval vessels on Lake. Ontario, as well as gunboats, were built here. Although various unsuccessful British and Indian expeditions fell back to Carleton Island, and the guns and troops from Fort Ontario (Oswego) were transported here when that position was abandoned; we can find' no record of any military or naval action having been fought at Carleton Island. Technically ceded to the U.S. by The Jay Treaty in 1796, Carleton Island was still in British hands at the outbreak of the War of The garrison at that time consisted of "a sergeant and three invalid soldiers, and two women." When news of the outbreak of war reached Cape Vincent on the New York shore, Captain Abner Hubbard, with another man and a boy, sailed over to

3 - 2 - capture the Island, in what was the first seizure of a military post after the declaration of war. Soon after, the barracks were burned and the island abandoned as a military base by both sides. The earliest reference to the wreck in North Bay that we have so far been able to find is a map dated 1810 which indicates a wreck in the approximate location where our wreck is to be found. We have as yet found, nothing that positively identifies this vessel or accounts for its being there. Our research to date indicates that it might be anyone of as many as ten or twelve possible vessels. Accurate measurements after excavation will undoubtedly narrow the choices to no more than four or five. We have every hope that our research group will give us a positive identification. Certain artifacts were found during a preliminary investigation of this site. A pewter uniform button from a British regiment known to have been active in this area during the Revolution and a British naval cutlass of late eighteenth century pattern were found, with some cannonballs (both round, bar and grapeshot) buried in the sand amidships of this vessel. It is our opinion that these finds leave little doubt as to the age and ownership of the vessel. The vessel lies in ten to twelve feet of water. The upper portions of her hull have completely disappeared. The lower portions of her stem, sternpost, and some of her ribs protrude above the bottom. At some time (and we have no idea when) after her sinking, a large amount of sand, stones and gravel were dumped onto the remains of the vessel. This was apparently an attempt to use her as the base of a wharf. This mound is highest near the center of the ship, reaching within five to six feet of the surface. This covering has served to protect the bottom of the vessel from decay; and we have reason to believe that her keel, keelson, ribs, bottom planking, and her ceiling planking inside the ribs are fairly sound. She was a two-masted vessel. Both mast steps protrude from the stones and sand. The Underwater Archaeology Committee of the New York State Divers Association proposes to undertake the project of learning all that we can about this vessel by means of research and by means of careful excavation and recording. With the cooperation of the Office of Parks and Recreation, we have erected an underwater grid over the vessel, and have nearly completed the where our wreck is to be found. We have as yet found, nothing that positively identifies this vessel or accounts for its being there. Our research to date indicates that it might be anyone of as many asten or twelve possible vessels. Accurate measurements after excavation will undoubtedly narrow the choices to no more than four or five. We have every hope that our research group will give us a positive identification. Certain artifacts were found during a preliminary investigation of this site. A pewter uniform button from a British regiment known to have been active in this area during the Revolution and a British naval cutlass of late eighteenth century pattern were found, with some cannonballs (both round, bar and grapeshot) buried in the sand amidships of this vessel. It is our opinion that these finds leave little doubt as to the age and ownership of the vessel. The vessel lies in ten to twelve feet of water. The upper portions of her hull have completely disappeared. The lower portions of her stem, sternpost, and some of her ribs protrude above the bottom. At some time (and we have no idea when) after her sinking, a large amount of sand, stones and gravel were dumped onto the remains

4 - 2 - of the vessel. This was apparently an attempt to use her as the base of a wharf. This mound is highest near the center of the ship, reaching within five to six feet of the surface. This covering has served to protect the bottom of the vessel from decay; and we have reason to believe that her keel, keelson, ribs, bottom planking, and her ceiling planking inside the ribs are fairly sound. She was a two-masted vessel. Both mast steps protrude from the stones and sand. The Underwater Archaeology Committee of the New York State Divers Association proposes to undertake the project of learning all that we can about this vessel by means of research and by means of careful excavation and recording. With the cooperation of the Office of Parks and Recreation, we have erected an underwater grid over the vessel, and have nearly completed the detailed charting of the site as it appears before the start of excavation. The following sketches illustrate the construction of the grid, and the design of the movable subgrid. EXCAVATING TECHNIQUE: In planning and executing this project, we have three major goals in mind: The first and primary goal is the discovery and recording of historical fact. What is this ship? How did it get here? What can we discover about the part it played in the events of its time? Our attack on these questions takes two forms: intensive research in libraries and archives, and the physical investigation of the ship and the artifacts it contains.. The second major goal is the recovery and preservation of all artifacts that maybe found within or near the ship. This of course involves extremely careful inch-by-inch excavation and the recording and identification of each object found.. The primary tool to be used in this excavation is the human hand. "Fanning" with the hand is the gentlest method of removing mud, sand, and gravel at a rate that will allow very small objects to be uncovered without being disturbed or damaged. Fortunately, there is usually a slight current to carry away the sediment stirred up by this method. By positioning himself facing the current, the diver will always have a clear field of view. Excavation will start at the ends of the ship, and either or both ends may be worked, depending on the direction of the current. Our third major goal depends to a large degree upon successful realization of the other two: We would like to I raise and preserve whatever remains of the ship itself. We have some rather unique ideas as to a method of accomplishing this relatively 1nexoensively. This will be the subject of a later proposal to the State. This report will concern itself only with the techniques of excavating the site and recording the artifacts found. Prior to commencement of careful excavation, it is necessary to remove several tons of rocks weighting up to 200 lbs each. An underwater dump truck, as illustrated in Figure 4. has been constructed and tested. It will carry up to 300 lbs. of stones at a time and can be easily transported

5 - 3 - and dumped by a single diver. In choosing a dumping site, we considered the possibility that any area so used might itself contain valuable artifacts. We finally chose a shallow rocky area near shore where our searches so far have disclosed nothing of interest. Sand and gravel that has been displaced by "fanning" will be removed periodically with an air lift. We have found that a small air lift will function well even in water this shallow, so long as its outlet is not raised above the water surface. We will construct a floating screen as shown in Figure 5 so that all gravel br0ught up by the air lift maybe checked for artifacts before being discarded.. In developing a method of working and recording an underwater "dig", many factors must be considered that have little or no pertinence to a dry land operation. Aside from the factors peculiar to working underwater, there are many variables that differentiate one underwater site from another. Differences in depth, water clarity, bottom type, or current may make techniques that are ideal for one site completely inappropriate - or even impossible at another. The shallowness of this site facilitates communication between diver and surface, and imposes no limitation on diving time. The limited clarity of the water greatly reduces the utility of photographic recording techniques. We feel that photogrammetry is impractical at this site because we cannot cover more than one-fourth of a five foot square at a time. It would take 336 photographs to record just one level of the 84 - square grid. Important items will, of course, be photographed before being moved. Due to the nature this site, we are situation. Being of the fill that has been dumped on dealing with a rather unusual bottom a mixture of stones of all sizes with gravel, sand, and silt, it is much more cohesive than the usual bottom composition. We believe that we will be able to excavate stratigraphically, starting from either end and working on a nearly vertical exposed face. We hope that it will be possible to determine the interface between the fill and the ship's original ballast. We also hope that examination of the various types of debris at this interface will give us an indication of when the fill may have been deposited. The almost complete absence of current, and the protection from wave action in the bay promotes diver mobility, but limits the possibility of working more than one or two divers simultaneously because disturbed silt dissipates slowly. On the Project, we have endeavored to establish an approach that adheres as closely as possible to standard day land techniques so that our work may be easily evaluated by those familiar with those techniques. At the same time, our familiarity with underwater work in general, and this site in particular, has led us to certain modifications in standard technique. There is no question that the accurate recording of the locations and relative positions of artifacts at an underwater site is much more difficult than on a land "dig". Surveying and photographic techniques are fairly simple and straight forward ashore. Underwater, these techniques have been adapted with some success: Line-of-sight leveling and photogrammetrical mapping have been used

6 - 4 - at ocean sites with good visibility. We do not believe that these techniques are applicable to a site where visibility is often less than six feet and good photos cannot be taken from more than three feet away. I We have therefore decided to use the more time-consuming method of sketching the location of each artifact and bottom feature with soft pencil on styrene plastic boards printed with a replica in scale of the 25 square foot movable sub-grid. When the sketching of. a 5 foot square, on each side of the board has been completed, the board is passed up to the topside recorder and either traced or photographed, or both. It is then erased and' set aside for reuse. Instead of line-of-site leveling, we are using a direct-measuring technique that seems to be very practical at this site. Since the cables will sag somewhat over their span and will undergo a cycle of stretching and retightening, we will not attempt to use them in determining elevations. Instead, we are using a float-supported steel tape a illustrated in Figure 6. Since there is usually very little wave action, the water surface provides a very stable datum plane. The design of the float is calculated to minimize the up and down motion imparted by whatever small waves are present from time to time. The steel tape is removed from the float, soaked in alcohol, dried, cleaned, and re-oiled after each day's use to prevent it from rusting out too quickly. Day-to-day changes in water level will be observed on a scale affixed to a grid pipe that projects above water at the bow of the vessel. At the start of each work day, the water level is noted, and any change is compensated by varying the point of attachment of the tape to the float. Thus, all readings by the diver will always be from the true datum plane, regardless of the actual water level. The grid constructed over the ship is 70 feet long by 30 feet wide. This encompasses the remaining intact structure of the ship and the rockpile over it. Due to the distinct possibility that detached portions of' the ship structure, equipment, and fittings may lie outside this grid, we have made provision in our numbering system to extend our operations for ten feet all around the existing grid. This extended grid would cover a total of 180 five-foot squares, or 4500 square feet of harbor bottom. The grid structure is such that it may be extended rather easily to cover this additional area. When excavation has been completed down to the inside of the hull planking, the entire ship will be measured, photographed, and detailed in both plan and elevation views. Unattached timbers or other positions of the hull structure that have to be moved will, of course be recorded in the same way as other artifacts. Since nothing remains of the decks, bulkheads, or between decks structure to hold anything in place, we feel that extremely exact pinpointing of artifact locations in plan view would be meaningless. Everything will have been shifted and jumbled to a considerable degree

7 - 5 - by wave and ice action and by collapse as the ship structure rotted away for nearly two centuries. In short, we feel that the level of accuracy obtainable by the grid design and recording techniques we propose to use is appropriate to this particular site. It is by painstaking examination of the layers of fill within the ship, and the recording of artifact locations in relation to these layers that we will learn the most that can be learned from this site. It is during the working of the exposed face of the dig that we expect underwater photography to be most useful. Close-up pictures of artifacts in situ will permanently record their position in relation-to the stratigraphy of the site. Sketch of grid system and diver recording data.

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