Well Paul, You really threw me for a loop with this one! Knowing your Boston location I checked the on-line rosters of every trolley museum on the east coast. It turns out that: A. I was on the wrong coast and B. This isn't an interurban!
Thanks to a gentleman named Bart Nadeau from the Yahoo Interurbans group who supplied the following information:
"That is Nevada Copper Belt 21, a Hall-Scott gas-mechanical car. Wood body was built by Holson Car Co. of San Francisco in 1911 for an engine by Hall-Scott Motor Car Co. of Berkley, CA. NCB was a steam shortline with this and a steel Hall-Scott for passenger service. It is now in the collection of the California State Railroad Museum."
I couldn't find a photo of it at the California State Railroad Museum site but did find it listed as follows:
"Nevada Copper Belt No. 21 Yerington Hall-Scott 1911 Gas-Mechanical Last operated 12/1985 at CSRM. Gift 6/1990 of Richard R. Reynolds. Oldest Hall-Scott motor car; operable."
I did turn up this photo of the car at the Northeast Railfan website:
Art Audley, AA3RT
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