The World War I Service Statement Cards, 1917-1919 (Department of Veterans Affairs), indexed by Washington Historical Records Project volunteers, are available and searchable online at the Washington Digital Archives.
Information contained in the records includes full name, serial number, race, place inducted, place of birth, unit assignments, ranks attained, engagements fought in, wounds received, dates served overseas, date of demobilization, and degree of disability (if any).
Choose Military Records from the drop down "Record Series" Menu. There are other Military Records online too. I searched for MASSEY and got these hits:
* Department of Veterans Affairs, World War I Service Statement Cards, 1917-1919 4
Pierce Military Records - 9 hits
* Snohomish Military Records - 11 hits
* Spokane County WWI Soldiers Miscellaneous Lists - 2 hits
* Washington State Department of Veterans' Affairs, Orting Soldiers' Home, Member Files, 1891-1987 - 4 hits
* Washington State Department of Veterans' Affairs, Veterans' Home - Retsil, Member Files, 1910-1977. - 1 hit