He may have re-written the original but he kept the misspelling of “descent.”
Perhaps this is what he had in mind:
descent
noun
1. the act, process, or fact of descending.
2. a downward inclination or slope.
Synonyms:
1. falling, sinking. 2. decline, grade, declivity. 4. ancestry, parentage. 6. assault, foray.
http://dictionary.reference.com/browse/descent