A basin carved from a single block of limestone, used in the production of gunpowder during the French invasions. The first incursion of Napoleon’s troops into Portuguese territory took place in 1807, and these invasions continued until 1814. Coimbra was occupied and plundered on 1 October 1810.
As an act of resistance, the Laboratorio Chimico dedicated itself to producing gunpowder for the city’s defending forces, under the supervision of the Chemistry professor Thomé Rodrigues Sobral (1759–1829), who became known as the “Master of Gunpowder”.