What is "insulating stool"

Insulate \In"su*late\, v. t. [imp. & p. p. Insulated; p. pr. & vb. n. Insulating.] [L. insulatus insulated, fr. insula island. See Isle, and cf. Isolate.]

1. To make an island of. [Obs.]
   --Pennant.

2. To place in a detached situation, or in a state having no communication with surrounding objects; to isolate; to separate.

3. (Elec. & Thermotics) To prevent the transfer of electricity or heat to or from (bodies) by the interposition of nonconductors.

   Insulating stool (Elec.), a stool with legs of glass or some other nonconductor of electricity, used for insulating a person or any object placed upon it.