When did construction begin on the Washington Monument?
1848
1884
1884
1884
1884
1884
1884
1884
1883
1884
1883
1884
1883
1885
1884
1883
1885
1884
1883
1885
1884
1883
1873
1885
1884
1883
1887
1873
1885
1884
1883
1856
1884.
1887
1873
1885
1884
1883
1856
1881
1869
1887
1873
1885
1884
1883
1884.
1856
1881
1879
1869
1864
1887
1873
1885
1884
1883
1806
1856
1881
1879
1869
1883.
1884.
1887
1873
1885
1884
1883
1865
1882
1856
1881
1869
1874
1887
1873
1885
1884
1883
1864
1883.
1884.
1806
1856
1881
1869
1879
1887
1873
1885
1872
1884
1883
1865
1882
1856
1880
1874
1864
1883.
1884.
1881
1887
1873
1885
1883
1884,
1806
1856
1861
1879
1869
1887
1873
1871
1885
1878
1872
1883
1883.
1884,
1884.
1856
1880
1880s
1890
1874
1864
1865
1882
1887
1873
1885
1883
1875
1806
1861
1881
1884,
1884.
1883.
1856
1879
1887
1873
1869
1871
1885
1878
1872
1883
1880s
1880
1890
1884,
1884.
1874
1864
1865
1882
1875
1881
1885
1883
1806
1861
1879
1873
1869
1884,
1884.
1856
1887
1871
1885
1878
1872
1883
1865
1880s
1882
1848
1880
1890
1874
1864
1884,
1875
1806
1881
1885
1884.
1856
1861
1879
1873
1869
1886
1887
1884,