The lowest and most level land areas show us, especially when we dig there to very great depths, nothing but horizontal layers of material more or less varied, which almost all contain innumerable products of the sea.
1564 - 1616
1803 – 1882
1854 – 1900
1942 – 2016
1928 – 2014
1835 – 1910
1869 – 1948
1884 – 1962
1898 – 1963
1929 – 1993
1879 – 1955
1809 – 1865