The brown QDL once belonged to a man named W. L. Ehrler. I wasn't able to find much about him except for a few articles written by a W. L. Ehrler via Google Books. I was able to track down where he was working in the sixties. W. L. Ehrler worked for the US Dept. of Agriculture in the Water Conservation Lab in Phoenix. He wrote, with fellow researchers, several articles about water retention capability in the leaves of rubber plants. It's interesting stuff to the people who find it interesting.
I sent an email message to the director of the lab and this was his response:
Yes, I would say it is very likely that the typewriter was once W.L. Ehrler’s, who was at the USWCL. I have attached one of his publications. Though he was retired when I started at the USWCL in 1984, I worked with both of the co-authors on the paper. I was told he passed away about a year ago in Scottsdale.While W. L. Ehrler is gone, his typewriter will live on. That'a a comforting thought.