Apergy is a fictitious form of anti-gravitational energy first described by Percy Greg in his 1880 sword and planet novel Across the Zodiac. It is also used by John Jacob Astor IV in his 1894 science fiction novel, A Journey in Other Worlds. Apergy can also be found in an 1888 article by Clara Jessup Bloomfield-Moore, called `Some Truths About Ke....
Found on http://en.wikipedia.org/wiki/Apergy


A fictional antigravity substance described by the author Percy Greg in his 1880 science fiction tale Across the Zodiac. Here are some extracts from the book that outline the concept: I had satisfied myself that only one thing needful was as yet wholly beyond the reach and even the proximate hopes ...
Found on http://www.daviddarling.info/encyclopedia/A/apergy.html
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