Except for when Dr. Morgan is sitting too close over the prostrate Mrs. Barton after her deep diving misadventure, Dr. Barton seems to have much more concern about Jed Grant through the whole picture - even before the obvious interest evinced by him.
Although, his wife would seem to be far more openly friendly with Tom Morgan, Bill Barton seems mostly oblivious to this (until the balcony scene, but even then his suspicions go right back to Grant soon after). It's almost as if despite all of his professional esteem and the wealth, he fears that Marcia will go for the blue-collar worker - even the one she goes out of her way to stay away from, while his fellow scientist (young, attractive, shirtless a lot, tight shorts) gets a pass for the most part.
I don't know if this was deliberate, but you can see an intellectual elite vs. common buff working man undercurrent going on in the Bill Barton characterization. In fact, I almost wonder if he'd give more than token anger toward his wife if she had in fact been caught sleeping with Dr. Morgan, while it's easy to see him being driven to double-homicide if he'd found her in Jed Grant's bed...
Interesting dynamic. I wish it had made for a more thrilling movie.