Roberval Cast Iron Balance Capacity:5kg Brightness-comparing Jolly's photometer using a

Brightness-comparing Jolly's photometer using a translucent paraffin disc method

used as a calcium and carbonate ion source in chemistry and geology experiments

5-inch porcelain plate drops into 20cm vacuum desiccators to support samples above the desiccant bed during drying and dehumidification

paired with sphere and cylinder counterparts to extend the electrostatic-curvature comparison up the size scale

Accurately measure current in circuits in real-time

Roberval Cast Iron Balance Capacity:5kg Brightness-comparing Jolly's photometer using aCast iron base Roberval balance with twin weighing pans, built for classroom demonstrations of mass comparison and mechanical balance principles.