A Non-Monitor Weapon Among Us

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A halberd recovered from Jamestown entered the conservation lab last week! We are assisting Colonial Williamsburg conservators with the treatment. The weapon consists of an axe blade (iron), a hook (on the opposite side from the axe), and the iron head is topped with a spike (the spike is bent, see picture below). The handle is ash with four iron bands nailed along the sides with copper alloy nails.

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Gun Tool Session

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This is a nice shot by Jason from photography of the three recently conserved Dahlgren gun tools: a sponge on the left, a Robinson worm in the middle, and a shot ladle on the right. Handling the objects during the photo session reminded us of how fit the gunners had to be to do their work. The ladle weighs 22 pounds empty and without the handle. The sponge head is 15 pounds. Ouch.

Silver or Not Silver?

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A beautifully preserved manometer was found attached to the engine. The gauge, which measures temperature and pressure, is currently under treatment. It has been dismantled as much as possible to assure better removal of the chlorides (e.g. the “conservators’ nightmare”). The main body of the gauge is made of copper alloy, and two wood stoppers enclose the top and bottom. The wood pieces are firmly embedded in the gauge and will therefore be treated intact and in contact with the copper alloy body. Former conservators carefully removed the mercury still in the glass component (see x-ray below), after which the glass part was separated from the gauge. This element is now fully conserved.

The scales were also separated from the gauge body and are currently being cleaned. They particularly attracted our attention because they seemed to be made of a silver alloy. However, the aspect of the corrosion products covering them was uncommon and the response of the metal to chemical cleaning tests was not what conservators expected from a silver artifact. Prior spot tests to identify the alloy were contradictory so it was decided to send one of the scales for an X-ray fluorescence analysis (non-destructive method) at the Northrop Grumman shipyard in Newport News. This silvered surface appeared to be a nickel alloy named nickel-silver or German silver. This alloy was mainly used due to its hardness and resistance to corrosion. Considering that 150ºF could easily be reached in the machines room, it makes sense that this alloy was used on a tool that needed to be readable at any time. Neat story!

What’s New with the Coat?

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As with many artifacts, finding the most suitable treatments for the wool coat involved exploring a lot of options. Ten cleaning methods and thirteen consolidation/drying techniques were tested and assessed on samples of the coat.  Quite a lot of work, but now we have them identified. These methods will properly conserve the artifact, be reversible, safe, and inexpensive. 🙂

The coat is getting cleaner and will be ready to dry sometime soon!

Another Day… Another Gun Tool!

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A shot ladle was recovered under the wooden chest in Monitor’s gun turret in 2002.  Consisting of a copper scoop nailed to a wooden head, it allowed the gunners to perfectly load/unload the Dahlgren guns.

The tricky part was not harming the copper part of the object during the wood stabilization and the wood during the metal treatment. Good time, beautiful artifact!