Puzzle Question (For the Week of October 19 - October 26)

What feature do all of the following words have in common:

     SIAMESE
     ESKIMO
     GUYS
     WIGWAM
     SEQUOIA
     MUSEUM
     SEISMIC
     COSMOS
     QUACK
     SQUEAK
     CUCKOO
     MESSAGE
     SICK
     COOKIE
     SAUSAGE
     SUCCESS