The Stonemason's Art

I noticed this amazing frieze above a doorway in the Lace Market. But what does it mean? My guess is that it relates to exporting lace, as the whole area was full of companies producing lace up until the recession in the 1980's. In fact I started off my working life for 3 years in one. Packing parcels of lace for companies like Marks & Spencer. These days all the old building have been turned into apartments, trendy bars and small businesses. No lace is produced here now. Another victim of the global marketplace & cheap imports.