I picked seven of these up in an antique shop, and I couldn't determine what they are. Maybe forestry insulators? It seems to be made of wet-process porcelain, and it was incorrectly fired as there are some protrusions similar to Akron "teat rests" but the firing rest is located on the "blades" of the insulator.

Markings:

Recess Embossed: WP4 Recess Embossed: {Indistinguishable patent number}

Please help. Thanks.