lot of 2 Vintage Christmas bubble lights

I was told that you can tell if they are vintage a glass slug in the tube that moves around. These bulbs have that. AND, you can test these by using a 9v battery. Just touch the bottom silver part to one terminal then tip the light towards the other terminal until the brass shank is touching. If both parts are touching their terminals, the light should come on. I wouldn't advise doing this to other kinds of lights that aren't the bubble kind, it could blow them out. These bulbs do light up with this procedure.