SEE US AT...

Issues Archive

July/August 2009 Vol. 13
No. 4
 The St Augustine  
  Lighthouse and Museum in  
  Florida. Picture courtesy  
  of Jonathan Zander  
 The Industry, a sloop  
  sent from New York with  
  supplies for the new  
  British colony, wrecked  
  off St Augustine in  
  1764  
 Chesapeake SonarWiz.MAP +  
  SBP software image from  
  Pancho Creek, a tributary  
  of the Tolomato River  
  which was cut through by  
  the North Beach Railroad.  
  This trackline connected  
  St Augustine with the  
  North Beach area in the  
  1890s. A popular tourist  
  destination, the Usina  
  family owned and operated  
  the railroad until well  
  into the 20th century.  
  LAMP recently  
  investigated the creek to  
  determine if elements of  
  a trestle exist in the  
  creek bed. It also  
  surveyed for remains of  
  historic watercraft sunk  
  in the creek. 
 SonarWiz.MAP + SBP  
  software image showing  
  one of the North Beach  
  Railroad abutments along  
  the Tolomato River and  
  debris associated with  
  its destruction during  
  the mid-20th century.  
WRECK PROTECTION  

By Brendan Burke, Lighthouse Archaeological Maritime Program, St Augustine Lighthouse and Museum, Florida, USA

Using sonar mosaics to protect US cultural heritage

 During the dark hours of an early summer night thieves worked quickly on the site, blowing a large hole in the seafloor with their propwash deflector. Exposing the pile of cannon, anchors and other wreckage their target had been laid open like a wound and was ready for looting. Lift bags or a derrick cable broke two of the guns away from their 235-year-old resting place and loaded them onto a boat. Only weeks later did divers from the Lighthouse Archaeological Maritime Program (LAMP) in St Augustine, Florida, encounter the looted site and report the theft to local and state authorities.

Looting shipwreck sites in many countries is illegal and strict legislation is in place to protect the publicly owned submerged resources. In Florida shipwreck looting can be a felony with heavy fines and prison sentencing possible. Moreover, after being looted, shipwreck sites lose their integrity as intact sites of cultural value. Future generations can no longer study them for their anthropological and historical value, or simply enjoy them as dive sites. Protection for wrecks is vital but worthless unless they can be monitored. 

To monitor these sites most efficiently, LAMP, the archaeological and historical research division of the St Augustine Lighthouse and Museum, purchased a Klein (USA) 3900 search and recovery sidescan sonar as part of our ongoing First Coast Maritime Archaeology Project. Since then, it has been used to monitor sites in northeast Florida as well as several other locations along Florida's coast. 

HISTORIC BACKGROUND 

St Augustine has been operational as a port since its founding in 1565. Known as the nation's oldest port, ships have been wrecking in and near its waters for almost 450 years. The cannon mentioned in the above paragraphs came from the oldest identified wreck in the area, a British sloop called the Industry. Carrying a cargo of seven cannon, several single-fluke mooring anchors and axe bits, the Industry had been commissioned by British authorities in New York to transport supplies to the newly acquired East Florida.

When the Spanish occupants of St Augustine uprooted and moved to Cuba as a result of the Treaty of Paris in 1764, new British inhabitants chronicled that they took everything with them possible, even pulling nails from doors. To strengthen its new outpost cannon were sorely needed to defend from seaward attack. Guarding the southern inlet to the Matanzas River this small fortification was constructed during the early 1740s. The Castillo de San Marcos, located in downtown St Augustine, kept ships at bay from the city's inlet but could not bring its guns to bear southerly enough to provide complete protection. Therefore, Fort Matanzas acted as the guardian of St Augustine's back door. Cannon aboard the Industry were bound directly for this fort. The mooring anchors were to be deployed along the city's waterfront for merchantmen and British naval vessels patrolling the coast.

After sailing down the coast, the Industry was blown aground on the St Augustine bar and soon came to grief. From this point onward the shipwreck sat undisturbed except by toredo worms and storms, and the ship's cargo remained surprisingly intact. Hull remains have never been found and it is possible that the cargo was essentially ‘dumped' from a broken hull with the ship itself coming to pieces. Period records indicate that debris was strewn along the shore, perhaps indicating the ship having broken up after the initial wreck.

In 1997 archaeologists in St Augustine discovered the wreck as part of a magnetometer survey. Most of the wreck was buried but tentative investigations had revealed its nature as a historic wreck. Excavations were planned to carefully document and retrieve artifacts for study. The propwash-created hole and subsequent cannon theft dashed these plans since the site was no longer undisturbed. 

Instead, archaeologists had to rely on salvage archaeology to recover what they could from the exposed and delicate site. Once the protective layer of sand had been removed artifacts could not survive the ravages of the sea. Fortunately many of the exposed artifacts were documented and removed for conservation and are now on display in our museum. 

ENTER THE TECHNOLOGY 

During January 2007 LAMP took delivery of the new sonar unit. As part of our remote sensing suite, consisting of a Marine Magnetics (Canada) SeaSPY Explorer magnetometer, a SyQwest (USA) StrataBox sub-bottom profiler (on loan from the University of West Florida), it completes our ability to fulfil standardised marine archaeological survey. The sonar's two principal duties are to survey the seafloor for shipwrecks and monitor known wrecks. In response to the looting of the Industry site LAMP ramped up the approach to protecting the submerged cultural resources around the nation's oldest port. Known sites have had their co-ordinates entered into the Florida Fish and Wildlife Conservation Commission's (FWS) chart plotters and prioritised as protected cultural locations. The FWS boats can monitor local sites from as much as 15 miles away, even while motoring in the opposite direction.

However, monitoring does not solely focus around illegal site disturbance. Heavy seas, sediment migration, erosion patterns and a host of other energy sources can have detrimental effects on archaeological sites. In fact, some of the more sensitive sites monitored in the First Coast area are inshore within tidal creeks, the Intracoastal Waterway or inland rivers. Given the long period of historic occupation within the region there are many known, unknown and unrecorded sites located at the water's edge. One site in particular has benefited from sonar monitoring and the data retrieved has added to the interpretation of the site. A site contemporary to that of the Industry is a plantation located north of St Augustine approximately seven miles (11 kilometres) up the Tolomato River.

After the Spanish re-took Florida in 1784 the area was host to a series of Minorcan yeomanry who utilised the riverbank for commerce and transportation; a community who also left tangible evidence of their occupation. A series of sonar transects performed during July 2008 identified piling-like objects protruding from the river bottom, possibly indicating the remains of a previously unidentified wharf or dock structure. This coming summer we hope to return to the site and dive on the piling to ascertain its true nature.

Moving offshore again and forward in time our focus turns towards a 19th century wreck tentatively identified as the Cricket. In June 1869 the steamer left Key West bound for New York. Her captain, AE Lozier, ran her north up the coast until she ran low on fuel just south of Cape Canaveral. By the time Cricket approached St Augustine on the night of the 15th she was, as an article in the New York Times stated, "on her last stick of fuel and forced to burn bacon". Low on steam she wrecked in between the outer and inner buoy, working in the heavy surf for three hours before her keel broke and Captain Lozier declared her a total loss.

In 1996 archaeologists began to work with a wreck identified during a 1995 survey that had an extant boiler, steam engine, propeller shaft, propeller and anchor. For the next few years divers took measurements and recorded the wreck in place. During the summer of 2007 LAMP divers on the site noticed that it appeared that the wreck may not be completely straight but the field season ended without this question being resolved. Limited visibility had previously prevented this observation. 

Not long after acquiring the Klein 3900 a monitoring trip to the steamship site was used to practise using the sidescan as well as our mosaicing software provided by Chesapeake Technology, USA. It was quickly noticed that no matter what angle the sonar approached the steamship wreck from there was a definite curvature to the wreck. Without physically excavating the keel structure of the vessel, it is plausible to say the keel is broken between the boiler and the engine. Since heavy equipment like this is usually placed amidships and low in the hull to maximise stability it is likely that the Cricket's keel broke where the most weight was present. 

This coming summer we will be working with the wreck as well as the adjacent ballast pile to learn more about both wrecks, especially the unidentified ballast pile to try and ascertain its age and nature. Without the ability to mosaic the wreck site and analyse sonar imagery from different directions, identifying the wreck's curvature would have been difficult at best.

As with any sidescan data, the individual files contain the high-resolution data for in-depth analysis. It is the mosaic, though, which allows us to see landscape data and integrate it into tiff-oriented programs such as GIS software and Google Earth for presentation-grade reports.

If you are interested, you can follow our research online at www.LAMPmaritime.org. Be sure to check out our blog, linked through the webpage, for recent updates on our fieldwork and findings and if you visit St Augustine please stop by the St Augustine Lighthouse to see our exhibits and visit with LAMP.

 

Back Issues

Article Search

© 2019 Underwater World Publications Ltd

Privacy Policy

Online Dispute Resolution

W3C XHTML Validated W3C CSS Validated Visit www.justice-roche.com