Sysmograph or Seismograph: How To spell?

The word Sysmograph is misspelled against Seismograph, meaning "An instrument for recording the phenomena of earthquakes."

Word contains consecutive vowels 'EI' in between alphabets s & smograph is misspelled as 'Y'
Wrong Spelling:  s-y-smograph 
Correct Spelling:  s-ei-smograph 
Find more incorrect spellings of Seismograph to spell right way.