I remember visiting the Rotolactor in action when I was a kid in the 1960s. There was a glassed-in booth where you could look down on the merry-go-round of milked cows, and there was a machine there where you could get chocolate milk. The Rotolactor I recall had fewer stalls than the ones in these photos.
I’ve seen the grave of Elsie/You’ll Do Lobelia, before it was moved.
http://blog.modernmechanix.com/rotolactor-milks-50-cows-in-12-minutes/
http://walkergordononline.com/history.asp
To my surprise, my internet search turned up a copycat in New South Wales, Australia, which apparently was copied from the one in New Jersey, and still exists!