Mathematical Instruments
Mechanical Instruments for Drawing, Measuring and Integrating
Drafting Instruments
Planimeters and Integrators
Alfred J. Amsler & Co.
Jakob Amsler
Polar Planimeter
Polar Disc Planimeter
Compensating Planimeter
Radial Planimeter (Durand-Amsler)
Radial Square Root Planimeter (Kent)
Radial Square Root Planimeter
Amsler
Integrators
Gottlieb Coradi
Hünenberger-Murbach
Various Makers