One piece of pink building material wrapped in cotton wool and white paper. The inscription on the paper reads: 'Piece of Roman wall cement from the Carys at Chesters (Mr Clayton's House and Park) or Cilurnum at Chollerford, Hexham; on the old Newcastle and Carlisle Road. 25 or 30 miles from Newcastle '.

This piece comes from a 14-drawer cabinet found in the Herschel family home in the 1950s. The contents of this and a similar cabinet seem to suggest that they were used by successive generations of the family to store specimens, material and apparatus for carrying out experiments.

Alexander was based for most of his working life in and around Newcastle and the location of this piece in the Herschel collection is almost certainly the result of his contacts in the area.

John Clayton (1792-1890) excavated large areas of the grounds around his family home, Chesters House and Estate, revealing a Roman Cavalry Fort, Cilurnum, a fort on Hadrian's Wall. He established a small museum with finds from this dig. Today, the site, including Clayton's museum, is managed by English Heritage and is open to the public.