Have you looked at the same areas on todays Google Earth? Do that and tell us what you see.
I couldn't find anything remotely resembling those symbols, so I'm just going to toss out a wild guess...
1- being in a ravine and on a creek, some sort of Mill.
2- Looks like some sort of transmission tower. if there are no others (such as for electrical or telephone), then I'd say Radio.
Again, those are simply guesses with absolutely nothing to base them on.