Signedunsigned
Inscribedon a piece of tape, handwritten: colorblindness / Holmgren Worstéds
FunctionThese bundles of wool were used to test for colorblindness. Frithiof Holmgren (1831-1897), a Swedish physiologist, invented this test after he suspected that a train engineer was colorblind, causing a well-publicized accident in 1876 in the town of Lagerlunda. Holmgren went on to test his theory on 266 employees of the Uppsala-Gäfle train line. He discovered indeed that 13 were colorblind. Holmgren's test became a reliable and standard routine check for railway and shipping employees.
For more information, see the following website at the University of Toronto.
ProvenancePsychology Department, William James Hall, Harvard University.