56.8 x 36 x 12.5
Carved and inlaid wood,
glass and brass
INDEX 1788 : V.III.323
Machina praecedenti similis: dissert tamen in eo, quod parallelogramum sustineat Prisma ad horizontem perpendiculare.
Instrument similar to the previous one: it differs in that the wooden frame holds the prism vertically.
This optical prism is similar to the previous one and is also mounted in a similar wooden frame, but here it is mounted vertically.
From Colégio dos Nobres, catalogue n.º 313.'s Gravesande, Willem Jacob, Physices Elementa, Leiden, 1742, Tomo II, § 3524, Tab. CXII, Fig. 1.