Location
Geography
Site Environment
Project Objectives
Introduction
On April 1, 1864, the sidewheel steamer Maple Leaf struck a Confederate torpedo
in the Saint Johns River and sank. Launched at Kingston, Ontario, in 1851, Maple
Leaf steamed on the lakes for eleven years. Most of that time her home port was
Rochester, New York where she was critically important to the economic welfare
of the city's commercial trade. In 1862 the Maple Leaf was sold to American
investors and leased to the Union Army for use as a transport on the east coast.
Her service paralleled that of many civilian vessels leased by the military
during the conflict. The Maple Leaf's sinking killed four crew members and sent
the personal effects of three Union regiments to the bottom. The cargo of
personal effects did not impact the Union war effort and the strong Confederate
presence along the river made salvage operations dangerous. The ship and cargo
were never recovered.
In the early 1980's a group of Jacksonville, Florida residents interested in
recovering Civil War artifacts began to search for the Maple Leaf. They found
the ship in 1984 but legal ownership of the wreck remained a question. The group
formed a corporation, St. Johns Archaeological Expeditions, Inc. (SJAEI), to act
as the legal entity in a planned attempt to win ownership of the vessel in
Admiralty Court.
The Maple Leaf was a civilian vessel leased to the federal government during the
war. After the ship sank, the vessel's owners were compensated for its loss
under terms of the lease agreement. This compensation gave title of the wreck to
the Federal government. The government defended their claim of ownership in
Admiralty Court with the Department of the Army acting as the government agent.
The matter was resolved in an out of court settlement between SJAEI and the
United States Government 1986. While the government retained ownership through
the agency of the Army, SJAEI received exclusive salvage rights. Recovered
artifacts would be split, with SJAEI receiving eighty percent and the federal
government twenty percent. The State of Florida would receive half of the
government share in return for any services given to the project (St. Johns
Archaeological Expeditions v. Maple Leaf and the United States of America,
1986).
SJAEI conducted excavations in the aft cargo hold during 1988 and 1989. Their
objective was to find material to conclusively prove the vessel's identity. This
work generated enormous interest and enthusiastic support from the public as
well as a small amount of grant money from the City of Jacksonville. It also
joined public and private sector interests into a continuing cooperative
scientific archaeological investigation.
During the late 1980's and early 1990's, acceptance of the Maple Leaf as a
legitimate archaeological project by the professional archaeological community
came slowly and funding was scarce or nonexistent. Finally, in 1990, the Florida
Department of State, Division of Historical Resources provided a Special
Category Grant through the Jacksonville Museum of Science and History to fund
research and the production of educational materials. The Jacksonville
Historical Society became the sponsoring institution for a second grant awarded
in 1991. With adequate funding secured, SJAEI sought professional assistance
from the Program in Maritime History and Nautical Archaeology at East Carolina
University to continue the research. State grants were awarded in 1992 and 1993
which allowed continued additional study.
Location
The Maple Leaf is located in Section 26, Township 4S, Range 26E, Duval County,
Florida. It sank at a prominent bend in the St Johns River off Mandarin Point,
11.2 miles (18 kilometers) upstream from Jacksonville, Florida. The hull lies in
the navigation channel, 2550 feet (777 meters) from the eastern shore,
perpendicular to stream flow with the bow pointing to the east. Water depth is
21 feet at high tide (Figure 1).
Geography
The physical terrain of northeast Florida consists of lagoons, estuaries, lakes,
rivers, coastal dune ridges, relict sand dunes, marine terraces, and barrier
islands. These features tend to be oriented on a north/south axis paralleling
the coastline. The sloughs and valleys separating higher areas are poorly
drained and many have wetlands and surface drainage channels.
The St. Johns River occupies a lagoonal valley formed as a result of fluctuating
sea levels during Pleistocene glaciation. The valley began as a lagoon behind a
long barrier island during a time of higher sea levels associated with the
interglacial periods. As sea level dropped, the St. Johns River formed in the
shallow stranded valley. The Fig 1 large lakes characterizing the present river
formed in depressions of the lagoon (Clewell 1991:19).
Site Environment
The St. Johns River, the longest river in Florida, is unusual in North America
for its northward flow. Its headwaters lie in the marshes of St. Lucie and
Indian River Counties. It flows 480 kilometers north along the Atlantic coast
dropping only eight meters along the way (DeMort 1991:97-99). The river's
original water source is Florida's abundant rain fall which replenishes the
headwater marshes, collects as a surface flow, and drains into the river or one
of its tributary streams. The surface flow leaches tannin from decaying
vegetation accumulated in the marsh imparting a dark reddish-brown hue to the
water. This color is the defining characteristic that makes the St Johns a
blackwater river. Tannic water is often nutrient-poor, low in dissolved oxygen,
and strongly acidic (Clewell 1991:23). These factors are moderated at the site
area by tidal influences.
Due to the river's low vertical drop, the tidal reach extends over 59% of the
total length. The astronomical tides affecting Florida's Atlantic coast are
semidiurnal with two highs and two lows per tidal day. Flow reversal occurs with
each change and is influenced by wind, water density, freshwater inflow and
channel configuration (McPherson and Hammett 1991:32-35). These factors also
affect current strength at the site location. The measured and estimated
strength under the astronomical phase corresponding to mean tidal conditions is
1.4 feet/second (.83 knots/hour)(Bodge 1987:6-7). The highest tides, and
subsequently the strongest currents, occur during full and new moon phases.
These maximum current velocities have not been measured.
In the St. Johns' tidal area, vertical stratification is often present due to
density differences between sea water and freshwater. A dense saltwater wedge
flows upstream along the bottom with the tide, mixing with the fresh river water
above. The rate and amount of mixing is dependent on wind and freshwater inflow.
This often creates a broad transition zone from fresh to salt water (McPherson
and Hammett 1991:37). Wind is an important factor on the broad stretches of the
St. Johns where the open fetch can extend several miles.
At high tide the St. Johns River is 21 feet deep at the Maple Leaf site and the
intact main deck is covered by 4 to 8 feet of sediment. Only a few structural
features protrude above the river bottom to mark the site (Figure 2). The
largest visible component is the north-south oriented paddle wheel shaft that
identifies the amidships area. To the west, the rudder post marks the stern and
confirms the east-west orientation of the vessel. This alignment is consistent
with historical accounts of the loss (Murray 1864). Originally, no structural
features marked the bow, but diver activity has exposed the stem and pawl post.
The Maple Leaf site area is a marine estuary and strongly influenced by ocean
tides. Brackish water is normally present at the site location with salinity
ranging from 1.0 parts/thousand at low tide to 5.0 parts/thousand at high tide
in the Orange Park/Mandarin area (DeMort 1991:105). Salinity directly affects
the shipwreck through chemical processes occurring on exposed structures and by
dictating the type of marine Fig 2 organisms able to exist in the estuarine
environment. Of particular concern are the corrosion of the iron paddle wheel
shaft and ship worm damage evident on the bow rail now on display at the
Jacksonville Museum of Science and History.
The river bottom surrounding the site area is a flat featureless plain of
gelatinous, highly organic sediment. The sediments consist of sand, colloidal
silt, clay, and organic matter. The top stratum is a soft mud described as fluff
(Duncan 1994:126). A sample of the material contains 25% sand size particles and
75% silt and clay size particles (Bodge 1987:12).
Flocculation is the main cause of sediment deposition at the Maple Leaf site.
Clay, silt, and organic matter are the primary components. Organic matter is
supplied by plant detritus from the surrounding basin and from riverine plant
and animal organisms. Clay and silt come from weathering and runoff.
Flocculation increases in warmer months as temperature increases and the water
becomes less viscous. Lower water viscosity elevates the rate of fine particle
deposition (Duncan 1994:127-128).
Prior to deposition, the river carries the organic matter and colloidal clay and
silt as a suspended load, largely along the river bottom (Duncan 1994:127). In
the summer there is a noticeable suspended layer on the bottom, twelve to
eighteen inches thick. The layer flows across the bottom with changing tidal
currents. The suspended material settles out when the water is trapped in a
depression such as the large excavation units on the site. This situation causes
constant and immediate refilling of excavation units. In addition, man-made
debris carried along the bottom also settles into these depressions.
Visibility in the water column is dependent on dissolved tannin and suspended
load, while rain, wind and tidal flow have strong contributing impacts. Natural
light penetration can exceed 15 feet under ideal conditions but normally fails
about 10 feet below the surface. Artificial light penetration is dependent on
diver activity and suspended silt. It can range from zero to 5 feet. In the
suspended layer on the bottom, visibility is totally obscured and the problem is
compounded when sediments are disturbed. As a result, all excavation work on the
site is hampered by zero visibility unless the suspended silt layer is diverted
from the area.
Project Objectives
The Maple Leaf contains a unique legacy from the past, important as a resource
for Civil War history and maritime heritage. The National Park Service
designated the site a National Historic Landmark in the fall of 1994. The cargo
contains a material record of the American Civil War and those who fought in it.
Systematic archaeological investigation of the well preserved cargo is currently
revealing aspects of the conflict that do not survive in written form. The
vessel carried the personal belongings and camp equipment of three Union
regiments, sutler stores, and the headquarters equipment of General Robert
Foster. Since many artifacts can be traced to their original owners, the
collection offers insight on historical, sociological, anthropological, and
material culture questions regarding the Civil War and the mid-nineteenth
century. The Maple Leaf's undisturbed archaeological context will provide the
first opportunity to study a large Civil War collection with archaeological and
historical integrity.
The second major element of the site is the ship itself. This thesis will
concentrate on an analysis and interpretation of the hull and propulsion system.
The surviving structural and mechanical remains of the Maple Leaf represent
marine technology and commercial interest on the Great Lakes during the
mid-nineteenth century. The hull can provide information on marine architecture,
engineering, construction techniques, and internal arrangements including cabin
space and cargo stowage methods. It represents the typical vessel type that
carried a major share of passenger traffic and package freight on the Great
Lakes.
Archaeological investigations of the ship took place over three summers. The
field research included an examination of the existing vessel remains and
excavations in the forward and aft cargo spaces. The purpose was to collect
diagnostic data on the ship and create a baseline study to help guide future
research plans.
Specifically related to the ship, the investigation sought to determined what
parts of the vessel still exist and their structural integrity. Historical
documentation and several preliminary dives indicated nothing remained above the
main deck. After considering the ship's bi-lateral longitudinal symmetry,
excavation was confined to the starboard side. Working on the starboard side
also offered the chance to examine possible torpedo damage reported near the
starboard bow (Johnson 1864).
The project research design divided the main deck excavation into three areas to
be completed over three years. During the first year, 1992, the forward deck was
excavated from the bow to the engineering spaces. In 1993 the engineering spaces
were examined. The final year, 1994, the aft deck from the engineering spaces to
the stern was investigated. The research design also called for developing and
refining techniques to work on the low visibility site (Cantelas 1992; Van
Tilberg 1994).
The two primary elements of the ship are the wooden hull and its propulsion
system. Several important hull elements will be examined including basic
diagnostic construction features, the deck layout, deck furniture, space
utilization, and the longitudinal reinforcing system used to prevent hogging.
Although the propulsion system is badly damaged, remaining elements include the
boilers, power plant, walking beam, paddle shaft and paddle wheel construction.