I don't know what those tiny dovetails could be for, but given there are two, perhaps they were for scope mounts - seems improbable, I admit, but I don't have a better idea.
As I mentioned above, I know what the front dovetail is for, and it's not for a scope base. It's for a graduated scale to sit in front of the windgauge globe so you can see how far you're moving the globe sight.
Don't think a 1/8" dovetail could possibly be considered strong enough for scope mounts. I think it might be possible the rear is for a spirit level specially made to fit the tiny dovetail, but can't see anything similar in Roy Marcot's book on these rifles.
