This insulator is out of my collection. It is solid glass, smoky grey, dimensions are 6 ¾" x 4" Glassian says it is a "post insulator out of the Edison collection", what is a post insulator? Is that Thomas Edison?, see "insulator oddity gallery", page 9 /21. This is the only one I have seen…except for Glassian.

One thought was that it may have had a railroad origin. Does anyone know anything about it? Anything you can tell me about it about it would be appreciated.