Leseprobe

Julia Bienholz- Radtke Maria Lörzel “This substance is available water-clear, more or less opaque and in any conceivable colour. Its surface can be lent any conceivable pro- perties. One can shape it with a cutting knife, drill it, saw it, mill it. One can melt it, press it, blow it like glass, etc. In short, one can do anything with it. The process for the manufacture of transparent ana- tomical models that was made possible by the obtaining of the new material has been patented for the museum.” 9 › Material history of cellulose acetate, p. 81 In the mid-1920s, the laboratory technician and model builder Franz Tschackert (1887–1958), who had worked at the DHMD since 1913, pursued Lingner’s idea of producing a transparent anatomical model of a human being. 10 Based on already existing exhibition at- tractions like the “The Transparent Man” unit › Key objects of health education, p. 198 a new, completely transparent model was to be created from cellulose acetate. 11 In 1925, Tschackert commenced with production of the first Transparent Man, initially independently of the museum in the Siemank & Ringelhahn jam factory in Dresden with the simplest aids. 12 This process was described in 1973 in an eyewitness account of Isolde Seyfarth, the daughter of the jam fac- tory owner. 13 According to her statements, Tschackert used a natural skeleton for the construction, which he had assembled himself from the individual bones and attached to a metal frame. He modelled a human form with layers of straw and plaster. According to Seyfarth, Tschackert modelled the arms and legs after those of the factory owner’s son, which would explain the petite body shape of the first Transparent Men. Negative mould templates were derived from these models. Tschackert warmed the cellulose acetate plates in hot steam and pressed them with steam pressure into the mould templates. He used acetone as an adhesive, with which he solvated the joint faces. A solid connection then formed in the plastic after the solvent evap- orated. According to the eyewitness account, the internal organs were modelled after templates from a school. 14 Tschackert only reached an agreement with the DHMD about his continued employment in 1927 and relocated the manufacture of the not yet completed Transparent Man to the workshops of the DHMD. A total of eleven Transparent Humans were produced by hand here until 1946 – eight men and three women. 15 Each specimen was unique. The manufacturing techniques were constantly changed and refined. Technical innovations were introduced, such as a new alu- minium alloy for the production of the skeleton or an invisible electri- cal connection for the illumination of the internal organs. Due to man- ufacturing conditions, arm, head or leg postures could vary in detail. The unique appearance of single ribs, as well as the form of blood vessels are also individual differentiating features that today help with the identification and more accurate chronological classification of these Transparent Humans. 16 The DHMD was seriously damaged in the bombardment of Dres- den in February 1945. The middle part of the building that had been home to the “Man” exhibition unit with the first Transparent Man was completely destroyed. The workshops also burned almost to ashes. 17 20