I picked up these two pins at a local flea market for $3 each. They were screwed into a pair of Porcelain Products uniparts dating from 1953. Evidently, if they were indeed used in conjunction with those insulators, they are not all that old, but I am curious as to what they were actually used for.

Their composition consists of two wooden pins, just as you would ordinarily see on any telegraph line, but cut off around the shoulder, just a few inches below the base of the threads. The lower portion which has been removed has been replaced with a brass base. Inserted into the base, none too rigidly, are small bolts, as you would frequently find in anything machinery-related. And, attached to one of these bolts is a particularly strange nut - one with a spring-loaded mechanism of some kind attached to it. Any thoughts on their application or age? I was thinking either an indoor application, or some kind of substation one. The pins do not appear to be weathered to any great degree, but are obviously treated with creosote - something I would have thought would be reserved for insulators destined for outdoor applications.

Well - the verdict is in. Mr Jim Decker has told me that these are only part of an application - a variety of bracket known as a "Kindorf or Unistrut" channel. The spring on the nut is to hold the nut against the top of the channel. Thank you, Mr. Decker!