I recently met up with Art Cashin, director of floor operations at UBS and a regular on CNBC for years, on the floor of the New York Stock Exchange.

Cashin has been on the NYSE for nearly half a century. So I asked a simple question: How has this place changed during that time? 

He gave some amazing examples. Have a look (transcript follows):

Cashin: One of the things that they did to avoid bumping into each other was the idea that if you gave me an order that was far away from the market, I would send it out in an automated fashion -- back in those days, something called "pneumatic tubes." If you've ever gone to an old department store, or maybe even Brookstone, they take a report, and they put it in a little widget and send it off. Well, under this floor are acres and acres of little brass pneumatic tubes. They used to send orders that were away from the market.

It also had some rather strange and arcane sounding rules. In the summertime, and in the years before actually I got here, it was popular to wear straw hats of the kind with the hard brim. There was actually a rule that you couldn't wear a hat with a hard brim on the floor. for fear that. if I were rushing and you were rushing, we'd wind up poking each other in the eye with the hard hats.

Morgan Housel: So there were physical risks down on the floor back then.

Arthur Cashin: Sure!