Amsler integrator marked "RCS Maths Lab 770"
1900-1914
Integrator by Amsler No.162 in box
Hele-Shaw's integrator, engraved "G. Coradi, Zurich, no.16", with fitted case and accessories
1915
Amsler integrator in box
Amsler's integrator; in case with rail.
1856-1890