. >> host: sarah barrington gordon is professor of constitutional law and history at the university of pennsylvania in philadelphia and the author most recently of this book, "the spirit of the law" religious voices and the constitution in modern america. >> guest: thank you so much. up next week for for the start billing and special collections of the -- >> to climb up those steps and make your way in and then to arrive at the top of the steps and see the mezzanine filled with books and the bus, it's inspiring. i love when we have visitors that come in for the first time. they walk in the front door and usually if it's someone that is new to the building the first thing i hear is a giant oh and then the next work out of their mouth is oh my goodness, this is what a library should look like. part of what i find, sometimes overwhelming but totally gratifying is that this institution has existed for hundreds of years and every day when i come into work i get to contribute to history. the atheneum is this wonderful -- in the historic providence. we are one of about 17 membership libraries