Das Stereoskop und seine Anwendungen

By the begin­ning of the twen­ti­eth cen­tu­ry, stere­oscopy had expand­ed beyond pop­u­lar enter­tain­ment and was increas­ing­ly used in sci­ence and tech­nol­o­gy. Appli­ca­tions includ­ed astron­o­my, microscopy, pho­togram­me­try and stereo­scop­ic X‑ray imag­ing, where the per­cep­tion of spa­tial rela­tion­ships offered advan­tages over con­ven­tion­al two-dimen­sion­al images.
Hartwig’s book appeared in this peri­od of tran­si­tion. Theodor Hartwig (1872–1958) was a teacher of math­e­mat­ics, geo­met­ri­cal draw­ing and nat­ur­al sci­ence and was active in pop­u­lar edu­ca­tion. His inter­est in stere­oscopy was not pure­ly the­o­ret­i­cal: in 1907 he was grant­ed leave for fur­ther study and worked at the Mil­i­tary Geo­graph­i­cal Insti­tute in Vien­na, where he inves­ti­gat­ed a new stere­o­com­para­tor made by Carl Zeiss. The instru­ment allowed cor­re­spond­ing points in stereo­scop­ic pho­tographs to be com­pared and mea­sured with con­sid­er­able pre­ci­sion and became par­tic­u­lar­ly impor­tant in photogrammetry.
The pub­li­ca­tion itself reflects the edu­ca­tion­al ambi­tions of Teubner’s Aus Natur und Geis­teswelt, a long-run­ning series of acces­si­ble intro­duc­tions to sci­en­tif­ic and cul­tur­al sub­jects pub­lished from 1898. By sup­ply­ing Hartwig’s vol­ume with a set of actu­al stere­ograms, the pub­lish­er allowed read­ers to repro­duce the phe­nom­e­na described in the text for them­selves. The book there­fore doc­u­ments an impor­tant moment when stere­oscopy occu­pied an unusu­al posi­tion between pop­u­lar visu­al enter­tain­ment, exper­i­men­tal sci­ence and pre­ci­sion measurement.