Climatic changes arising from changes in the Earth's orbit and changes in its axial tilt are proposed causes of glaciations according to Esmark, in a paper published in 1824. There are three types important statements for the glacial periods. namely; chemical, geological and paleontological. Geological; This evidence of glacial periods comes in different forms, involving stone scrapings and scours, valley cuts, drumlins, glacial moraines, glacial erratics and till deposits. Consecutive glaciations tend to distort and erase geological evidence thus making interpretation difficult (Peltier)The paleontological; this evidence includes the geographic distribution of residual changes. Again, it is difficult to interpret because it requires a series of sediments that span a very long time, the range of latitudes, ancient organisms that, unchanged, survive for a few million years and whose temperatures can be diagnosed quickly and relevant fossil discoveries. Chemical proof; primarily includes variations in isotopic ratios in present-day fossils in sedimentary and sedimentary rocks and bases of oceanic sediments. However, this evidence may be contradicted by other influences exhibited by other isotopes