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Laboratory technicians tackled several larger and more complex concretions during February, resulting in fewer artifacts being processed but some fascinating discoveries.
In gross appearance, the geared jack resembles an old-fashioned automobile bumper jack, although it worked more like a modern hydraulic jack. The ram consisted of a slotted bar with a forged saddle on the end that made contact with the load. The bar passed through a gearbox, containing a gear that meshed with the slots on the ram. The gear was powered by a hand crank (missing) that enabled the user to apply or release pressure on the load. A wooden housing, also missing, provided a foundation for the jack that was placed on the load-bearing surface during use. It is likely that this jack was part of the ship carpenter's tool kit, used to effect repairs on interior structural members of the ship's hull. Numerous factors can affect the rate of corrosion of a metal artifact within a shipwreck. Neighboring artifacts may act upon the artifact as anodes or cathodes, galvanically protecting it or causing it to corrode to a more elemental state. Exposure to the seawater greatly accelerates corrosion of nearly all metals thus making it advantageous if the artifact is quickly buried within the bottom sediments (and stays that way). If only considering these two factors, in combination with a wrecking event, and 280 years of submersion within the dynamic environment of Beaufort Inlet, one can imagine why it is so difficult to explain, much less predict, the degree of preservation of an artifact embedded in concretion. X-ray photographs are also two-dimensional. It is impossible to determine the depth of an artifact within the concretion. For example, one large concretion, previously attached to Cannon #2 (QAR 232), was x-rayed several years ago and a large sail needle could be clearly seen in the photographic negative. It stood out bright and white against a background of darker iron bolts (darker because of their higher degree of permeability to x-rays relative to the brass needle). The needle was clearly of a more noble material and looked to be directly under the surface of the concretion. Upon attempting to retrieve the needle, only a forest of badly degraded iron objects appeared beneath the air-scribe tip. Fearing damage to these fragile artifacts, the needle removal was postponed and the concretion placed back in wet storage.
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Queen
Anne's Revenge
One
of the larger concretions, QAR 060, contained the iron components of
a large geared jack, identical to one discovered on the wreck of the
slave ship Henrietta Marie (1700). Identification of this curious
machine was made possible by David Moore, an archaeologist with the
One
of the most exciting discoveries was that of a flintlock gunlock embedded
within a concretion containing large amounts of lead shot (QAR 326).
The gunlock appears to be a standard flintlock although the cock exhibits
characteristics attributable to an earlier style flintlock called a
doglock. It is possible that this lock was repaired using a salvaged
cock. It is notable that the cock on the QAR 326 gunlock is nearly identical
to a solitary cock found on the 1717 pirate shipwreck Whydah Galley
(Hamilton 1992:261). It was quite a surprise to find a nearly intact
gunlock, considering the high degree of corrosion experienced by most
fragile iron artifacts from the QAR site. The QAR 326 concretion contained,
along with the gunlock and numerous lead shot, a number of corroded-nail
molds. It is unclear why the gunlock survived and adjacent nails corroded
completely, but differential preservation of artifacts is evident in
nearly all concretions. 
Radiography
(x-ray photography) is a valuable tool for the detecting the presence
of metal artifacts in a clump of concretion. Iron objects can be distinguished
from those fashioned of more noble metals (brass, gold, or silver, for
example) and their degree of preservation determined to some extent.
The results, however, must be viewed with caution. For instance, the
gunlock (QAR 326) did not show up in the x-ray photographs, due to the
large amount of lead shot in the concretion that shadowed the artifact
(x-rays do not penetrate lead).
The
QAR 232 concretion finally arrived at the Fort Fisher laboratory this
month and the sail needle retrieval re-commenced. Anticipating that
some of the iron bolts would be damaged during the excavation, the concretion
was photographed throughout the process to aid in the restoration of
the iron artifacts following chloride removal. After ten days of cleaning
with the air scribe and casting artifact molds as they appeared, the
brass sail needle was discovered nestled within a tangle of iron ringbolts.
The needle (QAR 232.014) is beautiful and at over six-inches in length,
relatively large. In addition to sewing thick canvas sails, it would
have been quite useful for sewing small canvas bags, the needle going
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