Can this crown design be used for dating an insulator? Thought this was a newer design and what Ken calls the smiley face [id=461871782] was the older.

Joe M:

Hi Masson,

That crown design with the pair of "C" shape top rests came to be at least during the mid 1920s, pretty much superceding the "half-moon" top rest design that you found on your large New England Power insulator (as you also pictured in one of your prior hunts). Yours surely looks like a Thomas without doubt and likely is 30s or maybe 40s.