Studied from its original page

Compound nomogram with pivot line

double-alignment nomogram · hinged nomogram · abaque à pivotement (d'Ocagne's Note O.30) · compound nomogram with pivot line

Made by: Maurice d'Ocagne; Joseph Lipka
Year: 1899-1930
Field: Nomograms and computing charts
Kind: Computing chart
Room: Charts that compute

Not shown here: its rights are not cleared

See the original page — fig. 117, printed p. 288 (archive leaf n312)

Test A passes (published 1921) and d'Ocagne died in 1938, but the nomogram is credited to C.-E. Wolff (Diagrams for Egyptian Engineers, Cairo 1903) and no death year for Wolff turned up in Wikidata or a web search.

The data it needs

z1, z2 input, first alignment · quantitative
z3 input, second alignment · quantitative
ζ intermediate, located on the hinge but not graduated · auxiliary
z4 output · quantitative

Built in 5 steps, as its maker described

ch. V §91, pp. 257–258 (fig. 106); §98, pp. 286–289, fig. 117 p. 288

Skeleton drawing, not the original plate

3 other forms share this skeleton

Source

Lipka 1918, Graphical and Mechanical Computation

Attribution checked against the source

Searches, not citations

archive.org commons.wikimedia.org scholar.google.com