South Carolina large group of bottles, all the same round bottom long neck blue tint
I'm pretty confident these are old, but wonder what the purpose of these bottles might be. They have some sort of mark on the bottom. Also if they may be related to the smaller round clear bottles I have found that have embossed Socony Vacuum (Mobiloil later), on the side but written upside down to the normal flat side down of the bottle. In the small bottle case, all of them found have the remnants of a screw type rim on the neck and they are broken off at that same spot. Any help appreciated. These were all found in or near the Waccamaw River, near the coast. 
Comments
I have a hunch you have been searching far and wide online to come up with a clue on these - I did the same and found nothing.
I suspect the answer will come from a collector of oil or petroleum related objects - search around using these terms: automobilia, petroliana, petroleum collectibles
The glass bulb screwed into some larger object with the threads facing down...possibly the innards of a early gas pump?