IDENTIFICATION OF AN ADHESIVE USED TO REPAIR A ROMAN JAR

A combination of micro-analytical techniques, including thin layer chr omatography (TLC), gas chromatography (GC), and combined gas chromatog raphy/mass spectrometry (GC/MS), was employed to study the lipid compo sition of an adhesive used to repair an Econ ware jar, recovered from Roman sediments of the River Nene as West Cotton (Raunds, Northamptons hire, U.K.). GC of the total lipid extract of the adhesive showed a co mplex pattern which was difficult to interpret. TLC was used to fracti onate the extract. The fractions were then trimethylsiylated and submi tted to GC and GC/MS. Betulin, lupeol, lupenone, allobetul-2-ene, and several other pentacyclic triterpenoid compounds were shown to be pres ent in the ancient material. The similarities between the lipid compos itions of the adhesive and of contemporary birch tar and a birch bark total lipid extract led to the conclusion that the adhesive was derive d largely from birch bark, thus providing the first firm evidence for the use of birch bark tar in ancient Britain.