From my fawlty memory:
It's about joining up with a bunch of folks, one by one, and taking them along to Washington Square to join the folk singers in the early sixties.

I can't quite recall the beginning, but here's a bunch of the middle, and the whole last verse:

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I said it's for the world to hear, come on to Washington Square. .
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In New Orleans we met a guy walking with no shoes.
And from his voice there comes a growl, he sure was singing the blues.
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I said don't waste it on the wind, come on to Washington Square.


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'till up ahead we saw the arch, gleaming white in the sun.
As far as all the eye could see, ten thousand folks were there.
And singing in sweet harmony, right in Washington Square.

Oh how about a dust bowl song, or the good old number nine?
And how about a (da-da-da) for the men who work in the mine?
The songs and legends of our time is gold we all can share.
So come and join the folks who stand and sing in Washington Square.

Mark