User:Phiramue/The Notker-Globe

The Notker-Globe is a combination of a terrestrial globe and a celestial globe, which was constructed in the Abbey of Saint Gall at the beginning of the 11th century. It's existence is documented by the monk Notker Labeo, who described the globe in the Codex Sangallensis 825 on pages 96 and 97 as a part of his commented translation of De consolatione Philosophiae by Boethius. In his description Notker indicates that this globe was used to demonstrate geographical and astronomical observations. Such a description of a combination of terrestrial and celestial globe is extraordinary for the 11th century. Indications of similar globes are mostly restricted to antiquity and then again the 15th century and later. Even though the spherical shape of the earth was well established in the early medieval period, scientist believed that it was simply impractical to build a globe, as the known world at the time would have only covered a small area of the surface.

Creation
The exact year of the creation of the globe remains unknown. However, it is estimated to be around the year 1015, as Notker has left several hints related to the timeframe of the the globe's construction. The first hint can be found in Notker's comment on the construction of the globe under the supervision of the abbot Purchart, who was abbot of the Abbey from 1001 until 1022. Furthermore, the timeframe can be narrowed down even more by looking at a letter written by Notker to Hugo von Sitten in 1017. In the letter Notker notes that he has finished his commented translation of Boethius, which contains his description of the globe

The construction of the globe is not ascribed to any single person. Rather, it is noted that the construction was accomplished in the abbey under the supervision of abbot Purchart. The creation was probably influenced by the celestial globes created by Gerbert d'Aurillac at the end of the 10th century. However, the Notker-Globe contained a significant change compared to the celestial globes of d'Aurillac. Notker's description was the first one of it's kind to reference an adjustable axis for a globe.

Description
Notker's description of the globe mainly elaborates on the use of the globe and contains no detailed physical description of it. The size of the globe remains unknown. In a first description of the globe, it is only referenced as a sphere, which Notker used to demonstrate his remarks on geography and astronomy. Notker further elaborates that the globe showed the locations of all the people and countries. This indicates the presence of a map of the known world on the globe. This map was probably more than just a schematic map, as Notker hints at the demonstrability of his geographical observations on the globe. Although the known world only covered a part of the surface of the globe, this did not mean that the rest of the globe remained empty. Notker describes the presence of Antipodes, who live on the opposite side of the earth. Furthermore, the terrestrial map was also expanded by the presence of the astrological signs, which were there to facilitate geographical and astronomical observations. This was also made possible by the globe's adjustable axis. Finally, Notker notes that certain alignments of the axis lead to only half of the astrological signs being visible, which indicates the presence of a horizon ring.