Sorry, no Charles in our line. If his wife died in 1918 it may have been from the Spanish Influenza epidemic after World War I. Some people say it was one of the contributing causes to the end of that war; everyone getting sick.

To find your Charles you might try the 1920 Federal Census, which is indexed by soundex. If you are located in the U.S., you can go to one of the National Archives and Records Administration (NARA) regional offices to look it up on microfilm. Also, some libraries have the census, though IF they do, it will be for local or state census. Good luck!