Four slide rules and ink drawing device

Lot 8549 limit € 20

2 x manufacturer: Aristo-Werke Dennert & Pape, Hamburg, slide rule model HyperboLog No. 971, with 1 instruction manual, as well as 2 x tear, each in original case, L up to approx. 34 cm, with ink drawing device Scribent, consisting of a total of 8 ink pens in different line widths and 2 handles, in the original case, not checked for completeness