Studied from its original page

Streetcar load model

Frankfurt streetcar load model · '1 Lamelle = 4000 Pers.' (handwritten on the model's frame)

Not shown here: its rights are not cleared

See the original page — Fig. 185, printed p. 225 (archive leaf n244)

Test A passes (published 1914) but test B fails: the page is Brinton's book and he died in 1957 (B would run to 2027).

The data it needs

from_node identity · categorical
to_node identity · categorical
route_geometry position on the base map · geographic
count value, quantised to one lamella per 4,000 · quantitative · passengers per 24 hours

Built in 4 steps, as its maker described

running head 'Map Presentations', pp. 224-226, Fig. 185 (p. 225); exhibited at the Internationale Baufach-Ausstellung, Leipzig, 1913

Skeleton drawing, not the original plate

55 other forms share this skeleton

Attribution less certain: contested, or no single inventor recorded