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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: 

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Year:  2021 PT id = 1186

Helix vs. Screw

Julio Antonio Gutierrez Samanez writes:

Until today, when they write about the work of Chancourtois and his telluric helix wound in a cylinder, still no one alludes to this other telluric helix wound in a cone or screw, the idea is the same: a rope that winds a geometric solid.

The first was devised in 1862, the other in 2008 (146 years later). But, there is a big epistemological difference. In the first, the elementary series presented was: 8, 8, 8, 8, 8 ..., etc., in the second it is: 2, 2, 8, 8, 18, 18, 32, 32. Furthermore, the division of conical radii is regulated by the function 2 (n ^ 2) = 2, 8, 18, 32...

Each binode has two spirals or two periods with the same number of elements, which correspond to the function 4 (n ^ 2). I don't think it is a discovery, it is just the conclusion of the contributions of Rydberg, Janet, and, of course, Chancourtois.

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