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The INTERNET Database of Periodic Tables

There are thousands of periodic tables in web space, but this is the only comprehensive database of periodic tables & periodic system formulations. If you know of an interesting periodic table that is missing, please contact the database curator: Mark R. Leach Ph.D.

Use the drop menus below to search & select from the more than 1300 Period Tables in the database: 

  Text Search:       

Year:  1866 PT id = 545

Spectroscope Revelations

From Scientific American in 1866, an article by Henry Draper concerning "The Spectroscope and Its Revelations".

At the time there was no understanding how the spectra were generated but it was recognised that every element produced a unique spectrum. Over 35,000 stars are catalogued/identified by their "HD" [Henry Draper] numbers:

Thanks to Eric Scerri for the tip!
See the website and Eric's Twitter Feed.

Also, thanks to Prof. Emeritus Robert J. Lancashire of The University of the West Indies for corrections & additional information.

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What is the Periodic Table Showing? Periodicity

© Mark R. Leach Ph.D. 1999 –

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