Cool finds. Probably some privys on those lots. Lately around here in Muskegon with any kind of demolition or construction the workers scarf up any bottles or relics that turn up.
Nice find. Try a fine scotchbrite pad dipped in CLR and lightly rub those rust spots. Should clean up nicely. I've done this on some nice stenciled stoneware and it works great. You can buy cheap toilet bowl cleaner for a buck at the dollar store. Use rubber gloves as it will burn your fingers...
Definately Pro Prohibition, probably around the turn of the century. Value around 10-20.00, would be a bit more with a city and state. Does it have a back label and or the glass stopper? I collect labeled half pint whiskies and might be interested in a trade or purchase.