CD 141.7 Twiggs Patent Insulator:

CD 141.7 Twiggs Patent Insulator top

CD 141.7 Twiggs Patent Insulator top

CD 141.7 Twiggs Patent Insulator

CD 141.7 Twiggs Patent Insulator

This rare insulator is marked with the patent date along with the Twiggs name.  It has two slots that the patent indicates would hold the wire and then a ball would be dropped into the socket to wedge the wire in place, one on each side.  The patent states "It is preferred to construct the insulator and the balls from glass" so it is doubtful if any were actually used in service this way as the force between a glass ball and the top of this glass insulator would most likely fracture the top.  Until recently there was only one Twiggs known, but 12 more have been discovered and appear nearly identical to the first.  It is not known which glass manufacturer made these pieces, but it is likely that they had not made threaded insulators before.


Return to the Timeline