From The Crop Circle Ship Wiki
An example of Hcc.
Note! As you can see above, an interesting aspect of the Hcc is that they are almost always aligned with tramlines.
 The relationship to Hydrogen
Above in part A, Hydrogen is shown normally, that is two small circles that have another area of still standing crop in the center. However part B is different in that there is (i) no standing crop in the center of the Hydrogen circles, and (ii) the existence of the Hcc symbols, thus suggesting the connection between the two.
A similar idea below is replicated again the same year, just before the Barbury Castle Tetrahedron appeared.
Here is part A there are circles with no standing crop, and in part B the Hcc symbols are almost implied as coming from the other part which is coming out from the Watersphere. The exact meaning is unknown, however it does show the relationship between Hcc and Hydrogen.
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