Mathematical Instruments
Mechanical Instruments for Drawing, Measuring and Integrating
Drafting Instruments
Planimeters and Integrators
Alfred J. Amsler & Co.
Gottlieb Coradi
Hünenberger-Murbach
Various Makers
Orthogonal Planimeter (Starke)
Polar Planimeter
Line Chart Planimeter
Hyperbola Graph
Harp Planimeter