Figures & data
Figure 1. Edgar Rubins’s Vase/face illusion (Citation1915/2005). Original published in Synsoplevede Figurer [“Visual Figures”] around 1915. Retrieved 2019–10-28 from https://da.wikipedia.org/wiki/Edgar_Rubin#/media/Fil:Facevase.png.
![Figure 1. Edgar Rubins’s Vase/face illusion (Citation1915/2005). Original published in Synsoplevede Figurer [“Visual Figures”] around 1915. Retrieved 2019–10-28 from https://da.wikipedia.org/wiki/Edgar_Rubin#/media/Fil:Facevase.png.](/cms/asset/279cd9cb-c067-4c90-8443-d97df1fa1f79/oaah_a_1802804_f0001_b.gif)
Figure 2. J. Jastrow’s (Citation1899/2006) “The duck/rabbit illusion” (original published in Popular Science Monthly 1899. Retrieved 2019–10-28 from https://commons.wikimedia.org/wiki/File:Duck- Rabbit_illusion.jpg#filehistory.
Figure 3. “The Kanizsa Triangle”. From Fibonacci (Citation2007), original by G. Kanizsa published in 1979. Retrieved 2019–10-30 from https://upload.wikimedia.org/wikipedia/commons/thumb/5/55/Kanizsa_tri angle.svg/768px-Kanizsa_triangle.svg.png.
Figure 4. Gustave Verbeek’s (Citation1904/2005) “A Fish Story” from The Upside Downs of Little Lady Lovekins and Old Man Muffaroo (original published in The New York Herald, around 1904. Retrieved 2019–10-28 from https://commons.wikimedia.org/wiki/File:Verbeek-rocanoe.gif.
Figure 5. Paired outlined foot soles at Boglösa in Uppland, Sweden, some of which can be interpreted as wheelcrosses. Photo Bertil Almgren. Shfa Bild- Id 12984.
Figure 6. Example of close spatial association between cows (bulls) and ships. Aspeberget, Bohuslän, Sweden. Photo: Bertil Almgren. SHFA bild id 11838.
Figure 7. Example of cows (bulls) with “ship-like” bodies. Runohällen, Bohuslän, Sweden. Photo: Bertil Almgren. SHFA bild id 11645.
Figure 8. Cows and ships in close spatial association. Note the almost circular shape of the horn on some of the cows. The connection through roundness is further strengthen by the cup-mark enclosed in the horn-formation of the animal to the bottom right of the photo. Torsbo, Bohuslän, Sweden.
Figure 9. Cows with horns, the horns are displayed differently, either in a naturalistic way or as a circle with a dot. Alvhem, Skepplanda, Västergötland, Sweden. Photo: Tomas Persson.
Figure 10. Close spatial association between circle images and ships. Lökeberg, Bohuslän, Sweden. Photo: Andreas Toreld. SHFA bild id 5158.
Figure 11. (a,b) The same motif viewed from two different stations points differing 180 degrees. On top, the carving displayed as a cow and below the same carving displayed as a ship. Torsbo, Bohuslän, Sweden. Photo: Peter Skoglund.
Figure 12. The panel at Alvhem, Skepplanda, Västergötland, Sweden. Original documentation in Rex Svensson 1982: 90.
