Perviousnes or Perviousness: How To spell?
The word Perviousnes is misspelled against Perviousness, a noun meaning "The quality or state of being pervious; as, the perviousness of glass."
Perviousness has double 'ss' in the end mispronounced as 's'Remember double 'SS' appears in the end of this word which should not be misspelled with single 'S'
Wrong Spelling:  perviousne-s  Correct Spelling:  perviousne-ss 
Check more misspelled words of Perviousness to spell it correct.