These are sermons by Robert Wells Kingdon, born 1903 and who preached in Hawaii and Wisconsin.
I (Jim Kingdon) got the versions in the SERMONS directory from Henry C Kingdon, including RWK-sermons-database.html and RWK-sermons-database.win. These are mostly in the format used by Microsoft Word circa 2001.
The contents of the hskingdon directory are from an archive of geocities. These are in HTML, and although they do have some dead links (geocities references and the like), they seem to be readable in web browsers despite that. Other geocities archives exist elesewhere on the internet and may also have this. Henry C says he used the the Word files above (or some slight variation thereof) to generate the geocities site.