Each 20 year section is a table based page.  Each page contains each year listed individually, with three columns.  The three current categories are Inventions, Companies and Political History.  This allows a dealer to find information that is relevant to that time period, and is extremely helpful in dating otherwise undatable items. Construction techniques, materials used, technologies are all examples of how to date an item, to the earliest time period possible. If it was originally welded and you know the date that style of welding originated, you have a good starting point.  Each fact and piece of information has been researched and rechecked.  However, due to the nature of dating historical facts, there are opinions and disagreements as to who or when the actual event took place.  This is a guide.  Please use it as such

. 1700-1719 1720-1739 1740-1759 1760-1779 1780-1799 1800-1819 1820-1839 1840-1859 1860-1879 1880-1899 1900-1919 1920-1939 1940-1959 1960-1979 1980-1999

The Source for invention dates, Company histories and political/historical information.  Need to find out when aluminum was found?  When did the light bulb first make its appearance?  Useful information to all Antique Dealers regardless of specialty!