All those 39 nice sharp drip points (OK, a few are damaged) ... Made in the age when they believed that drip points actually helped to drain the water and condensation from the insulator's surface more efficiently.
This insulator looks very Hemingray-ish, the color, the sharp drips and the embossing.
Л. О. (initials for as Лив. Общ.), Liv. Obshch. I believe the firm was named Livengov (or Livengoff)
This is an update of my posting from Feb 28, 2007.