Archaeologists working near the town of Xanten – an area of land which was a part of the Rhine riverbed for nearly 1,500 years – were thrilled to find an iron legionnaire’s helmet that had once been worn by a Roman soldier… and they were even more ecstatic to realize that the helmet held trace elements of glue on its exterior!
When researchers were handling the helmet for restoration purposes, they removed a tiny sample of metal with an extremely fine saw – not an unusual practice, since restorers need samples of ancient items in order to make sure the restorative chemical won’t damage the artifact – and were shocked to see that the tool’s heat was causing little silver laurel leaves that decorated the helmet to peel off, leaving threads of glue behind.
It seems that since the helmet was on the riverbed for such a long time, the glue was spared exposure to potentially destructive atmospheric elements, thus allowing it to maintain its adhesive power for over two thousand years.
Examination of other Roman artifacts since this discovery revealed that there are plenty of additional items – such as ancient battle masks – that have trace remains of silver decoration like the helmet’s laurel leaves, and it is likely that they were held on with glue in the same way. Unfortunately, a close look at many of the items has shown that they are too far in their deterioration to yield evidence of glue. However, it seems that the Romans preferred to glue on their decoration to battle armor, rather than go through the hassle of soldering on each and every small piece.
A chemical analysis of the ancient Roman glue has determined that it was made of beef tallow, pitch, and bitumen – but as of yet, researchers haven’t been able to exactly reproduce the adhesive, and are beginning to think that something like sand, soot or sawdust might have been added in order to complete the recipe.
Researchers are hopeful that they’ll be able to fully recreate the Roman glue soon – after all, if the Roman stuff can still stick after 2,000 years, it’ll easily surpass any of its modern competitors!
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Tomorrow: More Ancient Standard!