Ptolemy or optical factors and those caused by judgmental factors. He offered an obscure explanation of the sun or moon illusion (the enlarged apparent size on the horizon) based on the difficulty of looking upwards. There are several characters or items named after Ptolemy, including: [[File:Ptolemaeus - Quadripartitum, 1622 - 4658973.tif|thumb|"Quadripartitum", 1622]] [[Category:Ptolemy| ]] [[Category:100 births]] [[Category:170 deaths]] [[Category:1st-century Romans]] [[Category:2nd-century Romans]] [[Category:2nd-century philosophers]] [[Category:2nd-century poets]] [[Category:Egyptian calendar]] [[Category:Ancient Greek astrologers]] [[Category:Ancient Greek astronomers]] [[Category:Ancient Greek mathematicians]] [[Category:Ancient Greek music theorists]] [[Category:Astrological writers]] [[Category:Claudii]] [[Category:Egyptian astronomers]] [[Category:Egyptian mathematicians]] [[Category:Epigrammatists of the Greek Anthology]] [[Category:2nd-century people of Roman Egypt]] [[Category:Ancient Greek geographers]]
Lake Ptolemy northward flowing drainage and to the northeast by northeastward draining systems. The presence of "Asphataria" indicates that Lake Ptolemy was a freshwater lake, although with occasional brackish phases. Precipitation at the time was about per year. At a water level of Lake Ptolemy would have been connected with a paleodrainage system belonging to the Abyad Plateau. A connection between Lake Ptolemy and Wadi Howar is possible, but not proven. At water levels of Lake Ptolemy would overflow into Wadi Arid. Lake Ptolemy featured a diverse ecosystem. Plant species documented from Lake Ptolemy include "Acacia" and "Tamarix" species, as well as