A little slice of Springfield - in Swarthmore

I'm still looking for the answer to a question that popped up recently when I noted the arrival of our sign.

I talked about it last week in the blog and this morning in my Monday Letter From the Editor.
I declared that it marked the official "arrival" of the Daily Times in Swarthmore.

Which is great except for one thing.

Our new home - 639 S. Chester Road - is not actually in Swarthmore. It's serviced by the Swarthmore Post Office, hence the Swarthmore address. But geographically, it's actually in Springfield Township.

There actually is a little island of Springfield located down here on South Chester Road that is not connected to the rest of the township at all.

My question is this: Does anyone know how this came about? It sort of reminds me of the situation with Darby Township, where that town actually is split into two distinct pieces.

One reader replied that he was once told a local historian that the reason there is this small island of Springfield Township adjacent to Swarthmore goes back to the decision by the residents of what is now Swarthmore to form a borough and separate from Springfield. However, he offered the opinion that those residents did not want to have the quarry adjacent to what is now the Blue Route (behind the Swiss Farms Store) as part of their new burg. So they drew the boundaries without the quarry, and, he could not resist pointing out, without the blue-collar workers who lived nearby.

Anyone else have an explanation for this little slice of Springfield?

I'd love to hear it.