Sysmoscope or Seismoscope: How To spell?

The word Sysmoscope is misspelled against Seismoscope, a noun meaning "A seismometer."

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