Hmm...that vintage would be pre-numbers, so no model number under the grips. Actually, I've never seen one that old m'self.
Now, if I'm remembering correctly, the round butt frames of that era were Hand Ejectors, while the square butt frames were Regulation Police. Beyond that, I can't tell ya anything, I haven't laid eyes on it and don't know much about prewar Smiths in general.
There are a couple routes:
(1)
The Standard Catalog of Smith and Wesson. I'm sure someone who can lay hands on one will be along shortly. There's another one--very nice, information by model and then serial range--but for the life of me I can't remember the title.
(2) Repost in the "S&W Hand Ejectors" section on this forum. They'll know more. This is Concealed Carry.
(3) You can write Smith and Wesson directly. Firearms companies in general are very helpful when it comes to this sort of thing. They'll be able to tell you when it was manufactured, what the original configuration was (barrel length, finish and such), and perhaps even when it was sold.
Check out this post:
To IDENTIFY your Gun >
Good luck, and sorry for your loss.