Alongside a still active transmission line, I discovered the remains of a lower voltage line that ran on wooden poles. Some of the poles had been 'modernized' (more likely the original crossarms rotted away and needed replacing) with steel crossarms, of a few types.

Shown here is by far the most prevalent- the vast majority were badly mangled when the poles came down, and had their insulators removed- squirrels and chipmunks seem to have taken a liking to chewing on the lead threads. This particular arm was, at the time I retrieved it, the only example I'd seen in good enough condition to bother taking home.

If anybody knows who the manufacturer of this crossarm was, and/or the approximate era it's from, I'd love to hear what you know!