Something underlined

I came across a news story from July 1952 concerning a sighting of a UFO on US 81 south of Enid, Oklahoma. Sid Eubanks reported that a huge yellow-green ball swooped low over his car at terrific speed.

The link above is to the Victoria (Texas) Advocate. In another newspaper the article directly below this story was about Albert Einstein. "Einstein Not Curious About Flying Disks."
Physicist Albert Einstein is serenely unconcerned about flying saucers. Evangelist Louis A. Gardner wrote Einstein at Princeton to ask his opinion. Einstein replied: "These people have seen something underlined. What it is I do not know and I am not curious to know." This was the extent of his reply.
As far as I'm concerned, "something underlined" is UFOS (unusual figure of speech).