A note regarding Yolo County: the Woodland newspapers are on-line at Newspaper Archive. I did a quick search and there are over 1,000 articles that mention the name Horgan between 1890 and 1936. I have found that the Woodland papers covered the entire county and were very chatty about everything that went on. It is a very good source for lots of information. If you can't sign up for a trial membership, I would be glad to do research on specific people for you.