ILLINOIS WATCH COMPANY
Springfield,  Illinois
1869 -1927
(Sold to Hamilton Watch Company approximately 1928)

Illinois Watch Co made watches under several different names, including:
Burlington Watch Co, Chicago, Illinois;
Santa Fe Watch Co, Topeka, Kansas;
Also, the following watches were made by Illinois (although not exclusively)
Washington Watch Company (Montgomery Ward);
Plymouth Watch Company (Sears);

Remember, the serial number being referred to is the serial number on the movement (i.e. "guts") of the watch. 
Please note that ALL dates are approximate (estimates), and can be off by as much as 6 years or more.  The following is only a guide.

1872 - 5,000
1873 - 20,000
1874 - 50,000
1875 - 75,000
1876 - 100,000
1877 - 145,000
1878 - 210,000
1879 - 250,000
1880 - 300,000
1881 - 350,000
1882 - 400,000
1883 - 450,000
1884 - 500,000
1885 - 550,000
1886 - 600,000
1887 - 700,000
1888 - 800,000
1889 - 900,000
1890 - 1,000,000
1891 - 1,040,000
1892 - 1,080,000
1893 - 1,120,000
1894 - 1,160,000
1895 - 1,220,000
1896 - 1,250,000
1897 - 1,290,000
1898 - 1,330,000
1899 - 1,370,000
1900 - 1,410,000
1901 - 1,450,000
1902 - 1,500,000
1903 - 1,650,000
1904 - 1,700,000
1905 - 1,800,000
1906 - 1,840,000
1907 - 1,900,000
1908 - 2,100,000
1909 - 2,150,000
1910 - 2,200,000
1911 - 2,300,000
1912 - 2,400,000
1913 - 2,500,000
1914 - 2,600,000
1915 - 2,700,000
1916 - 2,800,000
1917 - 3,000,000
1918 - 3,200,000
1919 - 3,400,000
1920 - 3,600,000
1921 - 3,750,000
1922 - 3,900,000
1923 - 4,000,000
1924 - 4,500,000
1925 - 4,700,000
1926 - 4,800,000
1927 - 4,850,000
1928 - 5,000,000
1929 - 5,150,000
1930 - 5,300,000
1931 - 5,400,000
1932 - 5,488,301
1934 - 5,500,000
1948 - 5,600,000

- Information courtesy of PocketWatchSite.com

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